From Altitude Game: Wiki
These are all the maps that are made by members of the Altitude Community. They include all game types such as TBD, FFA, 1DE, 1DM, 1BD, TDM, BALL, and the non-official CO-OP. Feel free to upload your map and add a screenshot and a download link for others to use.
Downloading the Maps
To download the maps, right click the download link and select "Save As" (if you are using a PC) or "Download Linked File" (for a Mac) to save the linked map. By default, the file will be placed in the Downloads folder of a Mac when you download the map. Whichever platform you use, you should transfer the file after download to the Maps folder within the Altitude game directory to ensure accessibility by the program.
TBD (Team Base Destruction) Maps
FFA (Free For All) Maps
CO-OP (Cooperation) Maps
BALL (Plane Ball) Maps
TDM (Team Death Match) Maps
1DE (1-Life Demolition) Maps
1DM (1-Life Death Match) Maps
1BD (1-Life Team Base Destruction) Maps