As a native speaker of English UK, I would say, "before the bank" and it means you would first pass the petrol station (English UK), gas station (English US) or servo (Australian English). "In front of the bank" means opposite it/facing it" and so I don't think you mean that.

The dictionary is named "McGraw-Hill Education Essential ESL Dictionary". It's not available online except a preview on Amazon. I'm currently having an access to many ESL/EFL dictionaries and other such stuff. Some things have managed to surprise me at certain degree.

'Ahead of' only makes sense if you are moving. If you are heading north, and something is ahead of you, it is to the north of you. It doesn't make sense if you are not moving. "The gas station's one hundred yards ahead of the bank." would make sense if they were both on a train, and the gas station was 100 yards closer to the train engine...

What dictionary is that? Do you have a link? 3: doesn't make any sense to me. Even 1 seems a bit awkward to me.

The reason why I'm asking this question is that I found the following dictionary entry: before2 /bɪˈfɔːr/ [preposition] 1 In front of: Don't talk like that before the kids. 2 Earlier than: She came home before eleven last night. 3 Ahead of: The gas station's one hundred yards before the bank. The 3rd definition made me mad. I still don't understand the positional relationship(s) between the gas station, the bank, and the speaker.