Now, one stair was of course not enough. So, as the keenest amongst you could have predicted, we have elevators too (hey, it's a fantasy city).
The only way I found of making those is by faking a isometric-ish perspective (I know it is geometrically absurd, but what other way there would be?). This of course conflict with the rest of the map which will be top-down, albeit with shadows and reliefs. It was already a problem with the cliff anyway... but no, I am not going to try to do all the buildings isometrically in Ps. Hopefully once the city will be finished it won't be too jarring.