On Monday, March 30, 2015 at 11:21:23 AM UTC-7, bds wrote:
Years ago XCSoar used a DAT file format for terrain files and the old
terrain generator would create a file like filename-dem.dat

Can anyone here shed some light on the file format of those DAT files and
how they were obtained or created?

Thanks.

Bruce

The DEM files are created by geological surveys (satellite I think) here's the wikipedia entry:

http://en.wikipedia.org/wiki/USGS_DEM