I still like to keep certain things together on a level for viewing ease, but I've been going more and more vertical for efficiency.
Right now I've got a small surface keep with a ramp down to 1st stone level for depot. Keep roof has archery range. Walled courtyard around for refuse/butcher/tanner/bees/etc and an outdoor training barracks. Wardogs pastured throughout (although I haven't seen a kobold yet in 40.24...but they tear up the wild boar and honey badgers)
Ramp punches through soil levels but doesn't access them. Drawbridge at the bottom. The upper soil levels are channeled out for underground treefarm/pasture accessed from kitchen levels, which are the first 3 stone layers, and have a 2x2 central shaft with 4 10x10 rooms clustered around. Room has either 4 workshops with input storage surrounding them or is an output storage room. All crafting but metal/stone/surface(butcher/fishery/tanner) is done on these levels. Crafters assigned bedrooms attached to their primary workshop room. Also geese and pigs. Depot and goods storage as well.
Then I've got an aquifier plumbing level feeding mist generators through next few levels of living quarters and hospital well. Great hall surrounded by bedrooms/offices, tombs surrounding that. Next level down is hospital and jail, bedrooms. Another level with just bedrooms. These levels get haulers, soldiers, nobs.
2x2 shaft continues down, passes through but does not directly access cavern levels, all the way down to magma. This map was conducive to 2 levels of magma easily, so lowest has 8 smelters. Next above has 4 forges/2 glass/2 kiln. Ore/flux/coal/ingot storage integrated with the shops. Level above is standard 4 10x10 storage. Also nearby are mason/mechanic shops and planned obsidian farm.
Small booze and food stockpiles around stairwell drawing from main piles. Many stockpiles and a lot of micro-management setting them up, but it's all pretty efficient.
Cavern layer will get some fortifications and barracks when I get around to it. Right now I just dug a tunnel off the stairwell and punched a single fort to get spores.
I really need to learn minecarts and get some kind of an "escalator" setup. Researching that right now. Biggest inefficiency is hauling stone around.
So far I'm really pleased with the layout. It balances efficiency with aesthetics.
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