Karto
Tool to work on map data, to check the data and generate your own maps
...After that, you can add any points (GPS points) in the map to build your own map. You can also add a transparent GIF image in the map after calibration (cave, mines, roads, ...).
You can realize your own cartes with the data you add inside adding/showing/hiding layers of data.
You can import/export your data files (after checking and correcting them) in differents formats.