Campaign Cartographer 3, by Profantasy, is a CAD (Computer Aided Drawing) based program with tools especially suited to create maps. Though the basic program is ideal for overland maps (regional fantasy maps), it can produce dungeons and cities. Though Profantasy offers add-on software that specifically create dungeons (DD3) and Cities (CD3) - look at any of Gandwarf's work, that's all CD3 stuff.

Plus Profantasy has both existing add-on symbol content, and offers an annual subscription that provides monthly tutorials and additional symbols for different styles or types of maps.

Profantasy offers other applications, its best to visit: Profantasy.com site. Although if you were to order, use the link on the home page of this site, the Admin gets a small kick back for purchases made through that link.

For those who are more technically adept than artistic, its an ideal program for strictly mapping work.

Others here are more expert than I, though I too have the software.

GP