tinyE: There was a metro level in Duke DC, was that it? That actually lead to a secret time travel level that was pretty sweet.
Now that I think about it, I guess most of the Duke it out in DC levels rank as my favorites though some of them were clearly rushed in design.
InfraSuperman: Episode 3 of the original campaign does indeed feature an excellent level taking place in a subway, as well. It's called
"Rabid Transit".
And man, I really hope Sunstorm's Duke 3D expansions come to GOG some day. I'd love to try them, especially after seeing the excellent work they did with Blood's "Cryptic Passage".
darthspudius: I'm going to avoid Duke 3D and say my favourite Duke level is Duke Burger from Duke Nukem Forever. Such silly fun.
InfraSuperman: I recently played the Duke Burger level in 3D's "Plutonium Pack", which is also a lot of fun, albeit pretty damn difficult.
I agree, it is quite a kick in the balls.