UTM Topographic Maps was created by U.S. Army Map Service under the Viet Nam War (1964-1971), covered most of indochina area (Viet Nam, Laos, Cambodia) at scale 1/250.000, 1/100.000 and 1/50.000 and at scale 1/25.000 and 1/12.500 for cities area.
These UTM Topographic Maps are collected, scanned with a high resolution and stored in GeoPDF format, which easily to print out or opened as a referents background for editing, mapping or do a changing research.
Viet Nam is covered by 500 Map Sheets at 1/50.000 scale.
Digital Elevation Model 30m – the highest resolution topographic data generated from NASA’s Shuttle Radar Topography Mission (SRTM) was released globally by late 2015. The new DEM have been released with a 1 arc-second, or about 30 meters (98 feet), sampling that reveals the full resolution of the original measurements.
Here are the DEM Index:
The data format is TIFF file, and can be gennerated upto 10m interval contour line. Opencyclemap is a very good demo.