Old City
This is one of my favorite Lego cities, assembled when I was 14-15 years old. I couldn't keep anything like this set up permanently, because it was always on the family dining table, but this one lasted the longest, and was the most detailed. Unfortunately, because we didn't have a digital camera at the time, and film was prohibitively expensive, this is one of the only photos I have of a Lego creation from back then, and I only have it because I took it myself. I got the not-so-bright idea to cover it with baby powder to simulate snow, which made a much bigger mess than I anticipated.
The basic layout is a town that sits on a US divided highway, similar to many of the rural tiny towns I grew up near. The main road on the right goes to Washington, DC, I think, and features a number of rush-hour lane controls (I was utterly fascinated with Interstate 66 in Northern Virginia the few times I visited) and homemade traffic signs. Alongside it, there's a police station, horse farm, and a castle (every small town needs a castle with a dragon, duh!). In the extreme foreground, there's my house, a McDonalds with shoehorned playground, and I think the building that got cut off in the bottom right corner was my office, or something. And, in the top left, there's a bank and a pizzeria. The road on the left was supposed to be a curvy mountain road, with this town situated on its only connection to a larger highway.