DTED files have their origin in the southwestern corner of the DTED cell.
The grid cell registration is centered on that corner. Successive eastward columns are presented. The final value in the file is the value of the northeastern corner. DTED files have 1201 columns by 1201 rows, overlapping at their edge columns and rows with neighboring DTED cells. DTED Level 1 data are created from a variety of best-available sources.