When to use 'bei', 'an', or 'in' [duplicate]

Question

Is there a general trend or rule of when to use bei, an, or in when you are mentioning a place?

For instance this sentence: Der Zug hält am Krankenhaus. The train stops at the hospital. I thought bei was a more appropriate in this case. Der Zug hält beim Krankenhaus. The reason why I thought bei was more appropriate is because usually when first started to learn bei it is associated with buildings and such and an with smaller objects. But I've come across lots of sentences that seem to use them interchangeably.

For in am I correct in thinking that you use it when you want to express intent of entering a building or an object?

Answer 1

An means right at that place, while bei means near to it.

To get a grip of this, let's introduce a question. You are asking someone in the train for directions.

Wo muss ich denn aussteigen, wenn ich zum Theater will?

There are four ways to answer this using bei and/or an:

Der Zug hält am Krankenhaus. Das ist beim Theater. (right at the hospital/theatre near to the stop)

Der Zug hält beim Krankenhaus. Das ist am Theater. (near to the hospital/ theatre at that place)

Der Zug hält beim Krankenhaus. Das ist beim Theater. (near to the hospital/ theatre near to the stop)

Der Zug hält am Krankenhaus. Das ist am Theater. (right at the hospital/ theatre at that place)