To get that many z-levels, you'll need a wide elevation range and massive elevation variance. Try an elevation range of 100-500 with elevation variance of 1600. Turn off erosion, too.
Of course, this won't give you flat lands adjacent to incredibly steep mountains. You don't generally get those kinds of formations in reality.
As for design, the entrance and barracks should be in the mouth, noble quarters should be in the cranium, garbage dumps in the nose. Good luck!
What comes to the site, I have seen some that could support this. Make the adjustments described above, then set minimum volcano number to a high value (70-100 depending region size). This will generate a lot of small mountain ranges in the middle of forests and marshes (that are mid-elevation, resulting in a steep cliff), so you should find a cliff steep enough with relative ease.
Some time ago I had fort in a place that might suit this place very well (
Very steep mountain range, high volcano and HFS.) I had to abandon the place since the massive number of z-levels caused an enormous lag, even with the starting seven. Especially if anyone started to pathfind to the mountaintop.
So to keep lag at minimum, I propose the following:
a) Pick a very small embark
b) Do as much of the digging as you can near the mountain edge. It seems the game does not generate underground tiles until you mine into them, so don't go exploratory mining.
c) Block all access to the mountaintop, all those z-levels make pathfinding there really laggy.
d) If you have invasions on, beware of gobbos shooting down from the mountaintop. You can't do anything to them if they don't come down.
Maybe with Glass windows for eyes? 
Nah, glass floodgates. With magma behind them. Linked to a convenient lever so you can dump it on sieges and/or elven caravans.
I second this.
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Topic: Need Help with Mega-Project: Mt. Uristmore (Read 2286 times)