Garmin Custom Maps

Newer Garmin GPSs (including the 62, 64, Oregon, Colorado, Montana series, eTrex 20 and 30) allow you to use KMZ (Google Earth) files as custom map layers. You can now export CalTopo's map layers and use them with these devices.


The area you can cover with a download depends on the zoom level chosen. Approximate coverage for a zoom 15 (high resolution, 4 meters / pixel) download is shown below:

Account Level Tiles Size Good For
Free 256 9mi x 9mi Day Hike
Basic 800 17mi x 17mi 2-3 Day Trip
Pro 3200 36mi x 36mi 1 Week Trip (Garmin Etrex/62/64 only support 1600 tiles)

Create the KMZ file

  1. In CalTopo, click "Print" and then "Download KMZ or MBTiles File"


  2. Set the map background using the dropdown at the top right. You can combine layers as usual, e.g. "MapBuilder Topo" plus "Slope Angle Shading"


  3. Navigate to the area you want to export. Align the center of the area that you want to download with the approximate center of the screen. Zoom in or out so the approximate area you want to download is displayed on the screen.


  4. Set the Target Zoom level and click "Reset".


  5. The red rectangle is adjusted to the center of the screen at the zoom level you chose. The number of images and tiles for the area in the red rectangle and the chose zoom level is calculated. You can only fit a total of 100 images on a Garmin GPS.


  6. You can adjust the center of the rectangle by clicking and dragging the red dot in the center of the rectangle. If you have used the similar rectangle when printing, you will find that this rectangle does not have as fine a control.

  7. Click "Download KMZ"


Load the KMZ file onto your GPS

  1. Plug your GPS into your computer using a USB cable. It should show up as a removeable drive, just like a USB thumb drive

  2. Create a \Garmin\CustomMaps\ directory on the GPS, if it doesn't already exist

  3. Copy the .kmz file you downloaded to \Garmin\CustomMaps\


  4. Disconnect the GPS from your computer

Turn on the layer on your GPS

The following will vary between GPS units, but the basic steps are the same. These directions are for a Garmin 64st

  1. Turn on your GPS

  2. While viewing the Map, press the Menu button

  3. Select "Setup Map"

  4. Select "Select Map"

  5. Select "Custom Maps"

  6. If the file you just copied to the GPS is showing "Disabled", select it to enable it

Note: There is an issue with the Garmin etrex 30x. On this device, custom KMZ maps will not display unless you edit the "draw order" and place your custom layer above the base maps in the draw order. Additionally, set the Garmin map zoom is set at 0.8 mi or lower (the number may also be dependent on the size of the KMZ). Garmin's BaseCamp software shows the KMZ files correctly (at any zoom) and allows users to adjust the maps "Draw Order".