-1-Underground car-park: A quite spacious interior, but with lots of connections to the outside, including two wide openings. With some good fortifications this place can be well defended, and can act as a fine garage.
Some derelict cars may be found here, not too many raw materials though unless you go into the various buildings.
There are alot of additional alleys, some above and some on the same level, this environment is somewhat complex.
-2-Inner streets: Several alleyways and a dead end road that can serve as a car-parking area. The alleys here are long, and thus suitable for snipers.
Various materials can be found here, mostly furniture from the buildings and street objects.
-3-The Underground: Theories are this place was once the de-facto area to fortify against the zombie invasion, but lately word is the place has been overrun by zombies. A dangerous place by nature, if you can clear this one out, you may have perhaps the best area to hold off the zombies from.
Sadly, the place lacks good area for cars, and if your a sniper, you'll likely want to avoid this place, as the surroundings are tight and constricted.
Materials are abundant, barrels, furniture, and assorted trash can all be found.
-4-Hotels: ground level interior spacing that is somewhat similar to the underground, but more strung out, allowing snipers some breathing room. There is also a large area out back, However it has no access to the streets for vehicles so its use as a car parking area is not viable.
Materials are mostly furniture, there are some bum-materials around though.
-5-Warehouse district: A large stretch of area with loads of buildings to duck into. These buildings are rather spacious allowing for car-parking. And the openings are long.
Materials are abundant. You won't find much furniture, but crates are everywhere, wooden trays, barrels, and even some forklifts can all be found.
This place sounds like a paradise for holding out against the invasion, but beware, as the treatment plant is right near by.
-6-Treatment plant: A place surrounded by toxic sludge, everyone has heard rumors about this place. Apparently it's overrun by heavily mutated zombies, powerful foes that pretty much out class their basic zombie cousins by far.
People stress to stay far, far away from this place. If your crazy enough to try to settle down in here, you'll find very few materials, tight-ish interiors, and that horrible sludge. Not worth trying.
-7-Landfill: A open area swarming with flies, trash is everywhere, but doesn't make for very good fortifications. It's proximity to the treatment plant is another worry.
If you want to fortify this place, your going to have to assemble your fort completely in a makeshift fashion. Theoretically, if you can assemble some mobile vehicles, you could use this place to hold out very well. But you better have some brains on hand for that idea.
-yellow-Overpass:Survivors could potentially fortify themselves topside, but most focus below. Long open lengths allows for good sniping potential provided you fortify the massive amount of openings. Car-parking is quite abundant as well.
Materials are mostly barrels, crates, fences, and possibly furniture from nearby buildings. Quite varied.
-green-Canal:The most wide open area you'll likely find. The perfect dream for snipers. You could fortify inside the canal or on one of the few bridges. There is even a side area hidden inwards to the city.
Despite being a wonderful area for holding out, materials are pretty much non-existent. And unless you fortify on a bridge, car-parking will actually be somewhat tricky.
Again, a worrisome issue is this place acts as a funnel for mutants from the treatment plant... Good luck.