Next, set the map type and scale to match the desired results. In other words, if you are trying to send a 1:24,000 traditional USGS Topographic Map to the GPS, set the map type (on the Tool Bar) to USGS Topographic, Standard Edition, and set the map scale to 1:24,000 by typing in the scale desired into the drop-down control. (You could also select any of the preset scales, such as 1:18,056.)

Note that only a few map types can be sent to the GPS. These are: USGS Topographic (Standard, Shaded and Collared editions), Aerial Orthophoto (any edition), and Terrain Shading Only. Merged maps can not be sent to the GPS. If a non-exportable map is in view, the option to Send Current Map to GPS will not be allowed.

Also, be aware that even when some of these map types are selected, the map scale may be covering too wide an area for that type to be displayed. For example, aerial orthophotos cannot be displayed at scales greater than 1:18,056; set the map scale to 1:18,056 (or lower) to bring the Aerial Orthophoto into view (and enable the Send Map to GPS option.)

Once the area has been defined, and the map type/scale set, open the GPS menu and choose Send to GPS, Current Map. (Or right click on the map or selected area, and choose Send Map to GPS). The Save GPS Map window will appear.

In the Save GPS Map window, you can also specify if you wish to have your layers (makers, routes, tracks, etc.) embedded into the GPS map. For example, if you have used Terrain Navigator Pro's track tool to draw a trail on a topographic map, you may wish to have that trail always displayed on the GPS's version of that map. Embedding this layer allows you to do so. Note that all layers currently visible (as specified in the Layer Size/Visibility preference) will be embedded. Thus, if you want to have some layers embedded, and not others, use the Layer Size/Visibility preference to set up your map display to match.

Terrain Navigator Pro can also include a GPX file of Markers, Routes, and Tracks along with your GPS Map.

Manage GPS Maps

Because of the limitations on custom maps imposed by Garmin (more on this later) Terrain Navigator Pro also features a window that allows you to effectively manage your map content. This window is accessed by opening the GPS menu and choosing Manage GPS Maps (or by pressing Save and Manage in the Save GPS Map window.)

The Manage GPS Maps window presents a list of the maps you have created (using Send Map to GPS.) When you send a map to the GPS, a copy of this map is kept automatically by Terrain Navigator Pro. This can save you time in the future, should you need to remove custom maps from the GPS. The left side of the Manage GPS Maps window shows the maps that you have created in Terrain Navigator Pro; the right side shows the maps that are currently stored on the GPS.

To send a map to the GPS, highlight it in the list of Available Maps, and press Send to GPS.

The list of Available Maps also has buttons that allow you to Delete the selected map, retrieve Information about that map (such as its scale, dimensions, and number of tiles), Rename the map, Export the map (as a KMZ file for use in other applications), or to Send the map to Google Earth for viewing. Use these buttons to manage your collection of custom maps right within Terrain Navigator Pro.

The list of Maps in GPS can be configured to show the maps in the GPS, on the external memory card, or both. Unless otherwise specified, maps sent to the GPS will automatically be sent to the external memory card (if installed.) You can also remove the maps from the GPS and get Information about the selected map.

Video Tutorial Available

A brief video tutorial on sending maps to a Garmin GPS unit can be found on our YouTube channel.

About Tiles

Tiles are portions of map data. On a 1:24,000 USGS topographic map, one tile can cover just over 3 square miles. (Other map types and scales will vary proportionately.) Garmin has placed a restriction in most of its GPSs that only allow 100 tiles of custom maps to be displayed. (The newer Garmin Montana features a 500 tile limit.) It is important to note that this is not tied to the memory of the GPS, but rather its processing ability. Terrain Navigator Pro does not create this restriction.

As you create your library of GPS maps, use the Information button to note how many tiles each map contains. The display on the right will update in real-time with the number of map tiles that the GPS currently is holding. Once this number is exceeded, Terrain Navigator Pro will warn you that the GPS may not display the desired maps. (Note: for those connecting to the Garmin Montana using the GPSMap 62 setting, this indicator will show a maximum of 100 tiles; the Montana can safely store 500 tiles.)

We have discovered that the GPS favors maps stored on the SD Card before those kept in internal memory. Thus, if you have an SD card with 90 map tiles, and also have 20 additional map tiles in the internal memory, all of the maps on the SD card will be displayed, while half of the maps in the internal memory will be ignored. (Note that Garmin may change this functionality as they continue to revise and improve their products.)

If you prefer to think about your storage in terms of the number of 1:24,000 topo quads you can store on a Garmin GPS, the typical quad is 54.5 square miles. This yields a capacity of 18 quad sheets on GPSs with a 100-tile limit, and a capacity of 90 quad sheets for those GPSs (such as the Montana) that have a 500-tile limit.

Advanced Custom Maps: KMZ Files

While we have added many tools within Terrain Navigator Pro to create and manage GPS Maps for use with Garmin GPSs, we know that there are instances where you may wish to manage the maps yourself, or use some advanced features for map creation. Thus, in the Printer/File tab of the Print window of Terrain Navigator Pro, you can specify the export of KMZ files. For best results, set the Preview window to "Export Preview". Also consider starting with the Map Only template.

Once you have designed your custom map, press Export. On the GPS, the maps should be kept in the \Garmin\CustomMaps folder.

Map Storage

Terrain Navigator Pro keeps its GPS maps in the following Windows system folder:
C:\ProgramData\Maptech\Terrain Navigator Pro\GarminMaps

This folder can not be reassigned elsewhere.

Use Your Smartphone

You may want to consider using your smartphone instead of (or in conjunction with) a handheld GPS. Your Terrain Navigator Pro subscription includes access to the TNP Mobile App and features the same maps and photos offered on the PC desktop.