Spiral Staircase

To make a spiralling ramp you will want to cut the ramp into triangles (as seen from above). Then use the vertex manipulation tool to drag one corner of your wegde shape down, and do this respectivly with all your other wegdes to create a spiral slope effect.

The same process would be used for the steps, only you arn't limited to triangles for the sake of smoothing the surface. Create a wegde, and you can copy/paste it, then manipulate it in place of the next step.

The principles of these constructions go way back to Half-Life 1 mapping, before the advent of displacements for rubble/terrain or more ingenious constructions (concrete road in Half-Life 2, railway tracks in cp_badlands).

You can find yourself some good beginner construction methods over at the snarkpit. I presume it's still up and running..

edit: http://www.snarkpit.net/index.php?s=articles

That seems awfully complicated. I just use the arch tool. Size it however you want, then ungroup and lower each piece to 16 units above the previous step. Rinse and repeat to create a spiral. If you want to make it a ramp, simply cut the steps in half.

I was assuming one had already created an 'arch' using the arch option..

edit: I meant whole wegde segment.. thing. I couldn't find the right word for it. >.> 180* arch segment.

I had just woken up.. with a slight hang over.. heh.

I pass my buck to the tutorials there.

First, try make a bunch of ramps that go upwards in a spiral with 90 degree turns.

Now try walking up it and try telling me it's not the worst set of ramps you've ever walked up in a game.

See what I mean? You constantly have to turn, leaving you unprepared for any enemies, not to mention frustrated and/or bored. Just drop the spiral staircase.

Muffin' is right. It's better to have them go up/down parallel to each other. Like in most buildings you find.

Though, you might get away with it were it wide and a significant part of a flag room or something.

But it's a good thing to learn either way.