Door atop scaffolding

[Γαῖα]

Haven't played the originals for at least a decade but one thing has continually puzzled me in one of the games in the series still to this day.
During one of the games, lara climbs modern day scaffolding to reach a roof top. Once she does she gets to a point that there is a door on what i vaguely remember looks like a crossroad section.
When i approached the door back in the day it asked for a key. I never ever found that key or a video or tombraider walkthrough book that explained where it could be found.

Im wondering is the door still in the remake version, does it still ask for a key or has anyone found it ?

[webcider]

isn't that in Chronicles? this only contains Tomb Raider 1-2-3

[Γαῖα]

Im sure it was in one of the first three, maybe the thames wharf area. If thats so though then im wrong about scaffolding and it was a crane.
All i remember most is a cross section ontop a building with one of the sections having a door.
I guess i will have to replay the original three in the series to ever have any hope of remembering where it was (may have been a section your character isn't suppose to end up).
Thats not going to happen anytime soon though as my copies are on disk and my pc's nolonger have disk drives these days.

Thanks for the input though, much appreciated.