The Digital Obstacle File describes all known obstacles of interest to aviation users in the U.S., with limited coverage of the Pacific, the Caribbean, Canada, and Mexico. The obstacles are assigned unique numerical identifiers; accuracy codes, and listed in order by state. Please see the DOF Readme file for additional information.

The Digital Obstacle File (DOF) has moved to a new webpage.
Please follow this link: to access the new webpage and make a note of the new address. If you have any questions, please contact Len Morse at