From DwarfFortressWiki
[edit] Tile Colors
The colors of a map tile may give information about that region's predominant biome: its temperature, alignment, and other handy things. Cyan or blue means the area is "good" aligned. Purple and grey/red areas have "evil" alignment. Light grey, brown, and yellow areas usually are dry and have sparse vegetation. Green tiles have vegetation and are usually moist. White tiles indicate snow.
[edit] Legend
Tiles are listed in by alignment, with regular tiles first, then haunted, then good aligned tiles, and then evil tiles.
| Elven retreats
|
|
| Human cities and towns
|
|
| Dwarven mountainhomes and fortresses
Lighter colored fortresses and towns are more populous.
|
|
| Goblin fortresses
Pink ones are more heavily populated than the gray ones.
|
|
| Cave
|
|
| Ruins
|
|
Migrants