Installing Above the Timber 24K Topos on your Windows PC

Both the Demo and StateTopo.exe files are a self installing executable file with a series of dialogs to guide you through the install process. You'll be able to create a unique folder on any hard drive on your PC and the installer will create the appropriate pointers in the Windows registry so that Garmin MapSource and/or BaseCamp can view the map files.

If you have Windows Vista or Windows 7, you will likely get an "Installation Error" message when trying to install, re-run the install by right-clicking and evoking:  "Run as Administrator"


Installing Above the Timber 24K Topos on your Garmin GPS


If you've never used MapSource before, some of its conventions can be confusing. The following screenshots should help:

Of particular interest are the three movable toolbars below File - Edit - Find . . . Use the pull down dialog to select which map title to view. This image shows Washington's 24K Topos at a scale of 70 mi. You then use the Map Tool to select map segments. Note the pink squares (right) were selected using the Map Tool, the current active tool. These squares show up in the Maps table on the left. Only segments in this table are placed in your GPS receiver by MapSource. The table in this example shows maps from Arizona, California, Colorado, New Mexico, Washington and Garmin's US Topo - West. Any mix of map segments from various map titles are permitted, your choice.

After you've selected all the map segments you want from Wash 24K Topos, you can keep adding as many map segments from any other title in the pull down dialog. The maximum number of segments allowed under the Maps tab is 2025, See Note 2. It can then take MapSource an hour or more to build the map file. You can NOT add segments to the finished map file, you MUST build the entire map file at one time, See Note 3.

You can also use MapSource to create a Map Set Name, BaseCamp/MapInstall will only auto-name a Map Set. Any alpha-numeric string is allowed. The map set name will appear in many GPS receivers, particularly Nuvi units.

The view shows where four map segments come together. The lower-right segment has been selected with the Map Tool, the current active tool, and its name appears in the Maps tab, on the left. The bright yellow line shows a highlighted segment, if clicked (selected) it too would appear under the Maps tab.


  1. If you have an older Garmin GPS receiver (designed more than 5-years ago) it is strongly suggested that you use a card reader to load the maps, not a USB connected Garmin GPS receiver. If you've successfully uploaded large map files via USB, please ignore this note.

  2. Newer GPS receivers allow 4000 map segments. Beware that you can easily exceed the 4GB Fat32 file limit. If you exceed the 4GB file size, MapSource will waste 4+ hours building the map file before it sends the file to your SD card where it will then give you a file size failure.

  3. An alternative to building a single map file is to rename the map file gmapsupp.img to AnyName.img, all newer handheld GPS receivers support the anyname.img convention. Almost no Nuvi's support anyname.img. You can have multiple uniquely named anyname.img files.