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Why is it "two hours' journey"?

Why is it "two hours' journey"?

Chris333K
I usually pass C1 tests but this A2 test question got me curious. I got "BC that's how it is"when I asked my teacher.

101 comments

Any_Opportunity2463•
Everyone will say one or the other is correct but honestly? If anyone said any of these my brain wouldn't even notice anything was said "wrong". Literally this kind of stuff is semantics.
Some-Passenger4219•
Because it's the journey of two hours - possessive. The house of a dog is a dog's house.
AdreKiseque•
I get the logic. Possessive on hours, it's saying "journey of two hours". Sounds a bit more formal or antiquated to me, "two-hour journey" is more common around here at least, but it checks out.
Wut23456•
If you're using a possessive apostrophe but the word sounds exactly the same as if you didn't, then you add the apostrophe but not the 's' to the end
skalnaty•
It’s possessive - if you were just saying the journey is 2 hours long you’d actually drop the s: “it’s a two-hour journey” [here](https://www.reddit.com/r/EnglishLearning/s/GIfQY3eitI) is actually a link to another post about this exact question from a few months ago!
kfreed9001•
If (a) had been "a two hour journey," it could have been correct (maybe it would be more correct with the hyphen like (d) idk). However, with the options you are presented, "two hours' journey" is the correct one. My best guess as to why that is that since the journey takes two hours, the journey somehow "belongs" to those two hours: hence, "two hours' journey."
halfajack•
*None* of those options sound right to me as a native British English speaker. I’d say “It’s a two-hour journey to Paris”
Lexplosives•
You have two options for this in natural speech, and only one is present as an answer here (B). You might say that it will be "**a** **two-hour journey"** ("The journey to Paris takes two hours"). Alternatively, it would be "**two hours' journey**" ("Two hours of journeying will get you to Paris"), which is option B here. You're referring to either *a journey* as a noun, or *journeying* as the verb. The grammar of "two hour" reflects the form you've chosen. In the former example (a two-hour journey), two-hour is being used as an adjective, and thus should typically not be pluralised. In the latter (option B), "two hours" is a noun phrase, and the act of journeying is belonging to them (hence the possessive apostrophe). Does this make sense?
Chris333K••OP
I'm not mad about 2-3 mistakes but I'm just curious if there's more than "because that's how it is"
AmountWonderful7466•
Thing is what are you being "American English " or "His Majesty's English ".. 😒  I'm seeing two answers.. I use autocorrect for work (American English) and use the latter at home with my kids cuz that's what we learnt and continue to learn...
More-Environment834•
A two-year old kid Kid is Two years old
SquareThings•
No one I know would say any of those. “It’s a two-hour trip to Paris” with “two-hour” functioning as an adjective modifying “trip” is much more natural
UnableFarm259•
It seems to me that 'two hour' is functioning as an adjective here, modifying the noun 'journey'. Adjectives do not typically take the plural form in English, i.e. we do not say 'two reds cars? but rather 'two red cars'. So, when a noun functions as a noun modifier it takes the singular form. In contrast, if we express the same idea with 'two hours' functioning as a noun phrase then it does take the plural form - i.e. we would say 'a journey of two hours'. When we are writing we can choose to reduce the ambiguity of the modifier by joining multiple nouns with a dash as in 'a two-hour journey'. This is a reflection of the fact that English, unlike some other languages, reflects the function of a word more by syntax than by morphology.
Hopeful-Ordinary22•
He was a boy of seven years. It's a journey of six miles. I shot a stag of seven summers. He has a weight of eighty kilos. It was a film of about two hours. English does do an equivalent to a genitive of value/measurement/quantity, though this sounds increasingly archaic. This phenomenon can be used as justification for using possessive apostrophes in measurements of duration etc., whether or not it is the true origin linguistically or the rationale employed in everyday speech. You can use a similar expression for distance ("six miles' hard skiing") where something substantial in duration is measured in something other than time itself.
prustage•
All the options are wrong. In cases like this "two hour" is being used as an adjective to describe the journey not as a noun. So you would say "a two-hour journey" - without an "s" in the same way as you would say "a six-inch ruler" (not six inch**es** ruler) a two-litre bottle (not a two litre**s** bottle). However, you would still say "the journey took two hours".
littlemarika•
Really bad question. At least in American English almost nobody would say it this way. It sounds very old fashioned to me. I would say “It’s a two hour journey to Paris” if we’re sticking to this wording. In reality I’d say “It takes two hours to get to Paris”.
hassan_dislogical•
These aren’t necessarily wrong it’s just that we say it in different ways way more often. I’d probably say “it’s a two hour journey”
Big_Consideration493•
A two hour journey A hundred pounds Two hundred pounds You can, of course, have "an hour's journey" because "an" belongs with "hour", not "journey". You can have "a two-hour journey", where "a" belongs with "journey" and "two-hour" is an attributive noun phrase, functioning as an adjective (which is why it is the singular "two hour" and not the plural "two hours"), but you cannot have "a two hours' journey", at least, not in grammatically correct English. It is possible that preferring singular attributive nouns is getting eroded. Certainly it is more of a convention than a grammatical rule, and there are numerous exceptions that defy logical explanation (why, for example, do we say "women novelists" rather than "woman novelists"?), and that "a two-hours journey" may at some time in the future become standard English, but it is not standard English at this moment in time. So what kind of journey? Here the journey is of 2 hours So then the Saxon genitive for time can be used if you don't use an article except singular ( an hour's journey) Two hours' journey A two hour journey ( as in it is a two hour journey to York) Here the hundred or unit is acting as an adjective of quantity and adjectives can't be plural in English. This phenomenon - the uninflected plural of numerals - is a remnant of Old English. In Old English, words like hund "hundred" and Ăžusend "thousand" were indeclinable. That is, they did not change form based on case or number. However today we se things like " hundreds and thousands of people watched the Olympics" Or "Grandad sprinkles hundreds and thousands on his cereal" The noun or compound noun gets the plural or genitive. So: Nouns can act as adjectives and compound nouns too. " A two- legged cat" "4-wheel drive Here we can't put S as it's acting as an adjective Hundred and Thousand are generally indeclinable or uninflected and don't take plural You can use 's or s' Saxon Genitive with time phrases but it's not plural but possession and generally you don't use an article
tribalbaboon•
The apostrophe in "hours'" suggests possession so you can look at it like "it's a journey belonging to two hours" = "it's a journey of two hours". This works the same with other words aside from journey. You can say it's two hours' drive, or something like "I live two hours' walk from here". Despite what some comments are saying, it is correct grammar and sounds quite natural when used right
gridlockmain1•
To be honest I (UK native speaker) would never say that exactly, but I’d say “two hours’ walk” or “two hours’ drive” is fairly normal.
NightHardcore•
As a non-native speaker, I would say “It’s a two-hour journey to Paris”
arkapriya25•
Number-unit-noun/adjective, in this case Unit shall be used in single form- two-hour journey. Here two-hour as a whole plays role of adjective. As far as I know.
BizarroMax•
None of those are how we’d say this in the U.S. we’d say a two hour journey.
Krapmeister•
It's just a full days drivel away..
UnderstandingSmall66•
“Two-hour” is an adjective and must be use in singular form.
random_name_245•
It should be “a two hour journey”. Canada here.
Sebapond•
It is two hours of journey. That ' is acting as "of". It depends on the contex of the sentence and if you are refering to the lenght or the duration of the journey.
BrandenburgForevor•
The most common way I see it (American, Midwest) is: "It is a two hour journey to Paris" This is correct and acceptable but people might look at you funny for saying it: "It is two hours journey to Paris" EDIT: Both of these are pretty awkward ways of saying it so usually you hear: "It takes two hours to get to Paris"
Can_I_Read•
Gilligan’s Island is a “three hour tour,” so it’s not necessarily standardized, I’d say.
Juniantara•
To give the technical answer, is this case “hours” is possessive, because those hours were “owned” by the trip. However, as everyone has pointed out, this method of describing the duration is old-fashioned enough that I’ve never seen it use outside of older books.
Sykes19•
I know many correct answers are given, but I wanted to share that in my Midwestern, hick, farmer's dialect that I've lived around my entire life, C is by far and large the most heard way to say it. Any other way makes you sound weird. This subreddit is very interesting save effective at helping me learn what bad habits the people around there taught me.
Ok_Sentence_5767•
As a native speaker none of these really make sense. As a native speaker I would say "It's a two hour journey to paris"
xb806•
“A two-hour journey”. None of the options is correct.
Badtimewithscar•
Aussie English native, I wouldn't use *any* of those personally
symmetrical_kettle•
It's a journey of two hours. My best guess: if you're going to use an apostrophe to show possession (to replace the "of") then you rearrange it to say: a two hours' journey. Hours is plural, so we just add an apostrophe rather than 's. But as a native speaker (American), I would 100% say "a two hour journey." Not sure if it's grammatically correct, but IMO saying a "two hours' journey" does out you as a non-native speaker. I hear that phrasing most with Indians.
Thatwierdhullcityfan•
B is not right at all. If anything none of those are really correct. I’m from Northern England and I would just say “it’s 2 hours to Paris” the word journey is not needed. If the word journey HAS to be included then I would say “It’s a 2 hour journey”. I can’t really explain why, but using the plural “hours” is wrong. Just like if the drive took 30 minutes I would say “30 minute journey” instead.
lIlI1lII1Il1Il•
It should be "a two-hour journey." When we condense two or more words into an adjective, we use a dash inbetween, but the plural is typically lost. For example: * I ate a 2-pound block of cheese. * It's a 5-mile trip to Dallas. * He rode the 10-year-old car to the store.
caffeinated_panda•
American speaker. My understanding is that the possessive here is because it's a journey OF two hours. That said, I would never say "**a** two hours' journey". Either of these sound right: >It was two hours' journey to Paris. >It was a two-hour journey to Paris. I would only expect to see the first version in more stylized prose, though.
Deriniel•
imho there's also an error: hours' . I'm not a native speaker, but i never saw it, and i don't think it can be grammatically correct
Icarus_Flyte•
If you wanted to use "a" in this phrase I'd say you would also use the singular version of "hour". The phrase would then be either "a two hour journey" or "two hours journey". Adding the "a" changes its' subject (hours) from plural to singular. It's been a long time since I was in school so I've probably not explained it as well as I'd like.
Callinon•
The journey doesn't belong to the hours. It's a two-hour long journey (meaning the journey takes two hours to complete). It can also be a two hour journey which means the same thing but with fewer words.
boytoy421•
It's because hour shouldn't get pluralized because in this case it's like a descriptor. If you said "it takes 2 hours" that's pluralized but something like "it's a multi-hour trip"
Tanakisoupman•
Man I hate “proper grammar”. If you know what I mean then I’m using proper grammar goddamn it and I don’t care if some literary nerd says “erm, actually you need to add a hyphen between the ‘twenty’ and the ‘two’”
cardinarium•
There are two good answers: - two hours’ journey - a two-hour journey Only one is listed. The best explanation for why the possessive form is used here is that it’s “a journey **of two hours**.” That “of” historically called for the genitive. This usually only works for lengths of time, so no: - a three feets’ hot dog (use: a three-foot hot dog) - an eight pounds’ book (use: an eight-pound book)
dxmixrge•
I disagree with the quiz. In American English, I would say "It's a two hour journey." The "a" is necessary for it to sound natural.
joe_belucky•
WTF?!?!?
rainywind6259•
Murderers, they are killing me!
FatSpidy•
So, technically speaking, if you are giving the - 's - possession to a multiple or a word already ending in s then you use s' not 's. Therefore two hours' journey is correct. As the journey is being possessed by hour. Hour's journey. An hour's journey. The journey of an hour. And in this case you're stating a number of hours and then each of the hours possession. Two Johns' car. The car of both Johns. The car of either John. HOWEVER I would never use that expression normally. We'd simply say "It's two hours to Paris." since the time it would take is two hours of travel, and it's weird to give any form of time possession these days.
Kyosji•
Tow hours's'es jorney
buyingshitformylab•
nobody says that. It's a two hour journey to Paris.
SunshineSpooky•
Former copy editor and English professor: The apostrophe is possessive here. Basically, the implication of this particular phrasing is that the journey *belongs to* the two hours, like the timespan is an entity. It is "correct" but an unusual way to say it, and one that most native English speakers will not have thought deeply about.
TricksterWolf•
"Two hour journey" or "two-hour journey" would be far more common, but "two-hours' journey" is still correct. I know both are correct, and I know "two hours journey" is wrong, but I'm not sure why. I think "two hours journey" is wrong because "two hours" can't be used like an adjective in the plural form, maybe? But why does the possessive form work at all—does the journey "belong" to the two hours required to take it? I'd really like to know. Very surprising, but native speakers learn by inference and there are some things we know are always said a certain way, whether or not we know the underlying rule to it (if one exists). In this case it helps to know the theme song from Gilligan's Isle. :V
akittenreddits•
I agree with others that this is not how I would say this. I would say “It’s two hours to Paris” or “It’s a two-hour journey to Paris” but of these strange-to-say options, b is correct because two-hours is the possessor of the journey, because it can’t be an adjective if it’s pluralized. The apostrophe goes after the s (hours’ not hour’s) because both hours possess, not one hour.
FancyFrogFootwork•
It is a two-hour journey to Paris.
Larsent•
A problem here is that B is grammatically correct but sounds awkward and it’s not the way most people would say it. As people have said here, we’d say “it’s a 2 hour journey to Paris” which is not offered. But your exercise is a test of punctuation (apostrophes and hyphens) rather than common usage. Many native speakers do not know how to use apostrophes and even hyphens. But look on the bright side- you’re almost in Paris! It’s only 2 hours away! Only a 2 hour journey to the most fabulous city in the world!! Bon voyage!!
Brromo•
The question is wrong "two hour" or "a two hour" are both right, but hour should be singular
NotAllThereMeself•
It's A 2 h journey because its "a journey" and the 2h is a qualifier. It's two hours because two is plural. Relating to other people's comments: A lot of people will say two-hour but I'm not sure it's accepted by official grammatical rules. Parallel: you're 20 yearS old.
veryblocky•
Of these, only b is correct. But, I would pretty much never say that. Like others have suggested, the most natural is “a two-hour journey”
xpertbuddy•
In English, when we talk about the duration of time in a descriptive way (like describing how long the journey is), we use the plural form of "hour" and add an apostrophe after the "s" to show possession. So, it’s "two hours' journey" because you’re talking about a journey that lasts for two hours.
AirAdministrative686•
Even if it's the correct option, this doesn't sound right to me at all. I would say it's a two hour journey to paris.
TerrorofMechagoji•
As an American- the one you chose is the one that sounds the best to me. “A two hour journey” would be the best though
IckleWelshy•
They’re all wrong. Only way b would be right is if you remove the word journey
Historical-Duty3628•
a. Wrong because "a two hours" is incorrect. if 'hours' is plural it can't be referenced by a, which means singular. b. Fine. there are "two hours" means that hours is plural, but since the journey belongs to the hour (possessive), you would need to add 's to the word "hours" to show possession. In english, however, if you are adding an 's to a word already ending in s, the convention is to simply add the ' at the end, as written " hours' " c. Wrong because similar to answer a, if you simply have hour's you are referring to a single hour, which is incorrect becaus there are two of them. d. Wrong, for the same reason as a and d, adding a hyphen(-) does not indicate possession, nor plurality, plus there isn't such a thing as a 'two-hours' that could be referred to. It is not a noun. You can't say something like "I have a two-hours.", whereas you could say. "I have a hammer."
aliendude5300•
The reason a is wrong is because hours is plural and you're using the word a with a plural object, hours. These all sound awful though.
DharmaCub•
Because hours is plural and also possessive of the journey.
MiloKelpie•
The question doesn't have the correct answer listed, so you have to choose the closest answer. It still doesn't make any sense because it's not the journey's hours. Two-hour is the true, correct answer.
Environmental_Foot54•
In this case they are using the possessive on the plural noun ending in S (hours) for which you place the apostrophe after the word. e.g. four years’ notice, two hours’ walk If it was only one hour’s walk, it’d be as written here instead. That said, it’s a silly picky one and even most natives would choose another way to say this, or get it wrong.
mothwhimsy•
"A two hours' journey" isn't incorrect but most people would say "a two hour journey"
hunglowbungalow•
It's a two hour journey makes more sense... none of these look right
Vikingsandtigers•
The quiz is poor and the teacher is worse.
internetmaniac•
Yeah these are all wrong from my standpoint as a native North American English speaker. It’s “It’s a two-hour [drive, train ride, whatever, any word besides journey] to Paris”. You also could drop the hyphen.
Come-jive-with-me•
All the options are wrong? Should be two-hour singular.
psychophysicist•
“Two hours’ journey” is acceptable. It’s phrased possessively like the journey belongs to the two hours, a bit old fashioned but it’s an existing idiom. “A two hour’s journey” here the duration is used as an adjective modifying “journey” so it would not use the possessive “‘s”. “A two hour journey” would be fine. “A two-hours journey” again the problem is the “s”. Quantities used in adjectives generally do not use plural. “Twelve man jury” yes, “a jury of twelve men” yes, “twelve men jury” no.
2Maverick•
With "It's (It is)" and "journey" being included in the sentence, "a" should be at the front of the given answer. You don't say, "It is long journey to Paris," you say, "It is a long journey to Paris". They'll probably tell you to exclude the "a" because of the "two hours'" since the answer is B but that is also wrong, because the two hours is describing the journey, which in this context, two-hour becomes an adjectival noun, and therefore, the best answer would be "a two-hour journey," to Paris, which is what most native speakers will say. B seems acceptable, but it's not.
throwaway284729174•
A two hours is grammatically incorrect. "A" in this indicates a single subject, "hours" is plural. Because of this A and D are eliminated. (If D would have been singular "two-hour" it would have been correct as well. As others have mentioned.) C can also be eliminated with plurality it would have to have a hyphen and be turned into a singular item to pass. "Two hour's" is grammatically incorrect. It's indicating you have two identical things but use the singular label of hour. The 's and ' in B and C both indicate possession, and that's because time owns the action. I'm not sure why, but it is true. The action here is journey. B is left. All written out it reads "it is two hours' journey to Paris." Which can be checked by breaking it down to its core meaning. (Remove words without affecting meaning.) it is two hours' journey to Paris. (Journey can be removed). It is two hours to Paris. ("It is" can be removed). Two hours to Paris. As many have said this is overly formal. And would be a rare way to sting this concept together even in formal speaking let alone common conversation. As a Midwestern american I would usually say. "It's a two-hour trip to Paris" if I'm being formal and "it's two hours to Paris" if informal.
sapphyryn•
I’m a native speaker and I don’t get why “hours” is plural in the supposedly correct option. No one would ever say, “it’s a two hours movie.” “It’s a two-hour journey” is the only way I’ve ever heard it. Maybe the correct option in the image would be used in old-timey speech/writing.
Key-Thing-9132•
Short answer: Two nouns, Hour and Journey. In many instances two nouns will have a possessive, since one is measured by the other. You measure a journey by hours, and both are nouns. More examples of this 'two noun measure' rule: A day's pay A mile's worth of rope Two week's rent The city's skyline The ship's crew The mind's eye The heart's desire ETC. Although "two hours' journey" sounds unnatural to a midwestern person like myself.
sebastianinspace•
is it just me or is it easier to explain this to someone learning by just describing it like a relationship between a noun and and adjective? there are all these super archaic and complicated rules in english grammar that don’t make much sense with all the exceptions for specific things. i really think it’s much easier to explain it like: - blue sky (right) - blues sky (wrong) - two hour journey (right) - two hours journey (wrong)
saodevasao•
Explanation: The correct answer is b. two hours' journey because: When expressing duration, the apostrophe goes after "hours" to show possession (the journey "of two hours"). "a two hours journey" (a) is wrong because "two hours" needs to act as an adjective, and adjectives are singular (e.g., "two-hour journey"). "a two hour's journey" (c) incorrectly places the apostrophe, as "hour's" doesn't fit grammatically. "a two-hours journey" (d) is wrong because hyphenated adjectives describing duration should use the singular form (e.g., "two-hour"). From chatgpt Let me know if you'd like further clarification!
Intelligent_Jump_859•
This one is tricky. As an American, I believe you could have put "a" at the beginning and been fine. What's important here is the apostrophe. All the words are in the correct order. The apostrophe in the correct answer is possessive, when a word already ends with "s" you just put an apostrophe after with no extra "s" to symbolize possession. This is probably really confusing as a non native speaker because I can't really even put into words myself how exactly the journey is "possessed" by the "two hours".
fourstringtheorist•
The “-s” makes “hour” plural, and the apostrophe is possessive. (As in, “a journey of two hours” or “two hours-worth of journey.”) It is conventional in written English to omit the extra “s” with plural subjects when you would otherwise append “-‘s” for possession. (An alternate way to spell this phrase, which I believe is also acceptable, is: “It’s two hours’s journey to Paris,” but when you sound that out it looks like “hourses” which sounds a little too Gollum-like for my taste, haha.) At least, that’s how I, a non-linguist/grammarian, understand it.
atamicbomb•
B is technically correct but nobody would talk like that. It reads like an 1800’s novel and that style is no longer used. “It’s a two hour journey to Paris” is how a native speakers would say it . And A is the closest to how a native speaker would talk This is just a terrible question
atamicbomb•
Also, whenever a teacher says “that’s how it is”, that means they don’t know why it’s that way. I’ve had teachers say that to me for things that ended up being simply not true.
BhutlahBrohan•
i think these high level language tests are bonkers stupid. no one talks like this. why do they want to set people up to sound like huge nerds? i would say 'C' is correct, but i suppose the ' is in the wrong spot? but 'A' sounds completely wrong here.
BYU_atheist•
It's more formal. Informally, one might say simply "It's two hours to Paris", or as elsewhere in this thread, "It's a two-hour journey to Paris."
Old-Dish-4797•
Agree most native English speakers would not use this sentence. A more common example would be: “in two months’ time”. 
This_Acanthisitta_43•
I would say “two hour journey”. Grammatically correct does not mean native. If you follow the rules precisely you end up sounding un-natural. The rules were created to try to describe language not put in place prior to learning which is why they are often contradictory and confusing.
supermansales•
"It's two hours' journey to Paris" just doesn't sound natural in British English. We’d say "It's a two-hour journey to Paris." The possessive structure in the first example is outdated and awkward, technically correct in some old-school grammatical sense, but no one actually talks like that. At least, not where I'm from.
armahillo•
in american english, we would say “two hour journey”
Immediate_Order1938•
Incorrect - a (article) two—hour (adjective) journey (noun). Adjectives do not carry number in English. This is a common error, even made by native speakers when they over think the grammar: It is a two-hour journey. It is a three-day trip. Etc. Enjoy learning English.
Cheshire_Noire•
None of these are correct in my opinion, however, I can explain why this is the intended answer. It is "a journey of two hours" to Paris. They are using journey as a noun here, so they change to the the possesive, for some reason. Native English speakers do not talk like this (neither in America or Britain for the most part), but it is *technically* correct
Slothdoodles•
None of them feel correct, but 'hour' plural is still hour, so adding an 's' to it would be grammatically wrong. The apostrophe after the 's' indicates possession to the journey. For where to put the apostrophe I can't really help with a way to do it, it just comes to my mind that its just shouldn't be before the 's'.
uhhhscizo•
I think the issue here is that this is an overly formal way that some British people talk, like on the BBC or something. Where I live (Tennessee) it would be something like "It's a two hour journey to Paris." I think the apostrophe shouldn't be there, but besides that it is technically grammatically correct. However, "It's a two hours journey" isn't correct either. It really is no issue, though. This is an issue over very minor dialectical differences.
Leafar_08•
Your teacher is of no use with this one 🙏😭 Aren't teachers supposed to help their students understand ?
GyanTheInfallible•
“Two hours’ journey” sounds right to me but is somewhat formal. That said, I’ve said and written it hundreds of times before. You’ll more often see or hear, “a two-hour journey.”
Round_Skill8057•
This is a detail no sane english speaker would care about - the dash, the apostrophe, possession or multiple possession.... I guess it's B because the hours are plural and they (the hours) own the journey...somehow? But you could write it any of these ways and nobody would care a lick.
CourtClarkMusic•
It’s a plural possessive. This is slightly antiquated English, not many people use this particular frame of language these days.
Mrgluer•
this the type of shit that makes non english speakers still suck when they try to converse. it’s just wrong
Kaiti-Coto•
It’s “two hour” or “two-hour.” “Two-hour” is being used as an adjective to describe journey, and we typically don’t modify/pluralize adjectives.
ebrum2010•
As an American, I'd say either "a two-hour journey" or "two hours' journey". When you make "two hours" into an adjective it loses its noun status, thus it is no longer plural, thus "two-hour." For the second example, hour remains a noun, but it loses the article because if you say "a two hours' journey" now "a" is referring to hours (because hours is a noun) and you wouldn't use the indefinite article with a plural. You could say "a journey of two hours" and it would mean the same thing. You would also usually hyphenate it to show that it's one adjective otherwise two would be technically modifying journey and not hour. That's a technical thing, and nobody would read it wrong, but it's good practice to use hyphenation when you have an adjective and a noun become a single adjective to use a hyphen (eg "two-legged" "black-haired").
AfghanGuy2014•
it's "it's a 2 hour journey to paris". american muslim, from california