"The bank is behind the train station."

Translation: A bank a pályaudvar mögött van.

[EvaLschl]

Why is hátul wrong?

[mizinamo]

hátul is an adverb ("at the back") that stands by itself, not a preposition ("behind") that comes before a noun.

It would be like saying "The bank is at the back the train station".

(It does not mean "at the back OF...".)

[ureshiikame]

What's the difference between pályudvar and vonatálomás (not sure of spelling)? Do both mean "train station"?

[vvsey]

It would be "vonatállomás" but really it is "vasútállomás". That is railway station, not train station. But both are acceptable.

A "pályaudvar" is a major station, with many tracks. Terminal stations are usually all called "pályaudvar". A "vasútállomás" can be any stop along a train line, no matter how small. Major hubs along train lines, in bigger cities, are also "pályaudvar".

Btw, major long-distance bus (coach) terminal stations are also called "(busz)pályaudvar". Even though "pálya" seems to refer to a fixed track, like a railway track. "Udvar" means yard/courtyard.

[Brad288837]

Are buildings/places usually towards the start of the sentence? "The bank the train station..."

[MrtonPolgr]

I don't think it has much to do with buildings/places. As they say, Hungarian is a topic prominent language, so a sentence is structured as topic - focus - predicate (typically a verb) - rest. Here the topic is the subject itself, we don't have a "rest part" and the focus is the location itself, which is quite neutral with van.

[mZSLI]

is "van" necessary or can it be omitted?

[MrtonPolgr]

It can't really be omitted since we are using adverbs. For describing a location, you can't make a mistake with using van, although under special circumstances it's possible to omit (hol, itt, ott + certain word order)