Fellow Dwarfs, I give you the most stunning, impressive, massive construction ever made by dwarkind: Sungate, the Great Pyramid.
Map: http://mkv25.net/dfma/map-2856-sungate
Download Save: http://dffd.wimbli.com/file.php?id=206
Allow me to explain.
I started this baby way back when 33b was the new thing. I have worked on it off and on ever since then, watching it run ever slower as the object count increased.
I did cheat a little. I turned off sieges, artifacts, and all that nonsense. I upped the dwarf speed to 1 and turned off feelings when they started to tantrum. I still let them sleep, eat, and drink, though, and I never cheated in reactions to generate building materials.
The whole thing (above ground, anyway) is made from marble blocks. The marble was mined from below and then carved into blocks by hand by my faithful dwarf minions. Underground I continued the pyramid shape and smoothed all the stone floors.
I didn't do everything I planned to, because my computer started to choke. It now takes me about ten minutes to open the save, and fifteen to save it again (less if I just rebooted my computer, but seriously, how often can I be expected to do that?). See my points of interest on the map for explanations of some of these things.
I now consider it as close to complete as it will ever get, at least by my hands. My computer can't handle it anymore, and honestly, I'm sick of looking at the damned thing. But I think I should get some sort of prize for completing it after all this time. Like, money or something, right?
A note of warning! I finished it on my old version, 33d, and the save had a bug or two. When I upgraded from 33b to 33d, I stopped getting immigrants and caravans, and my dwarfs stopped having babies. (This is one reason I never upgraded it again). I did import the save to 38c, though, and it runs okay, though I didn't spend much time with it. You may be best off abandoning and reclaiming it to do any further work.
The most important thing about this pyramid is that someone uses it. I promised to build it a long time ago, and everyone was promising all kinds of cool stuff for it, but it's been a while and I'm frightened that all my work will be for naught. So please, if your computer can handle it, build me something beautiful! Make murals, create an adventurer's nightmare with booby traps, or just turn it into a thriving civilization, but use it, please, for the love of Armok, use it!
Location:
Shot of how many blocks were in use, about 90% of the way through construction: