Gtopo is a program for viewing the National Geographic Survey's
Topographic Map sets on a computer running linux
(or on a MAC running OS-X, or any computer with GTK).
I am not giving away the maps themselves, just providing an alternate piece of software. Gtopo uses GTK-2.0 and provides a simple and nice viewer for map images. The program was written in July of 2007 and is actively being developed. I am pleased if people download and use it and would be grateful to know how it works for them.
It now works quite well for viewing the TOPO! series files, and current development is focused on allowing it to obtain maps (and photos) from terraserver, which among other things, will make it useful for people who do not own TOPO! series collections (stay tuned!).
The following link is where I have collected a lot of reference information. None of it is essential reading if you just want to use gtopo, but it should be of interest to people who want to learn about maps, GIS, gtopo internals, file formats, Terraserver, the USGS MRDS database and more!
After using gtopo on my desktop for several years, I finally got around to rewriting gtopo in java to run on an Android tablet. This is a great setup. I am able to fit the files for the six southwest states into 16G of space, so it fits neatly on a 32G micro SD card. And my tablet (like most) has built in satellite GPS, so this works out wonderfully.
Gtopo / firstname.lastname@example.org