How to install bike maps on the Garmin Edge 520

Posted on November 22, 2015 in Cycling // 117 Comments

While writing my review on the Garmin Edge 520 I stumbled across what Garmin calls their ‘base’ maps. So for cycling these aren’t great. In my area they are the main roads on which bikes are mostly not allowed. So overall quite useless. However, the Garmin Edge 520 supports that you install your own maps! And, thanks to OpenStreetMap, you can get a detailed bike map of your region for free. Well, depending on how much data is available of course. But it’s not true navigation. You can’t tell it to navigate you to your favorite pub, but you can tell your Garmin to bring you back to the start and see whereabouts you are. Back to start is great if you feel like just going for a ride in an area you don’t know.

To install maps on the Garmin Edge 520 you need to take a couple of steps. The process is really easy and I’ll walk you through it with easy instructions. Please note that you choose to do this yourself. While it’s pretty much fool proof, I haven’t heard of anyone breaking their device doing this, I can not be held responsible if you do break your device.

Get a cycling map for the Garmin

First, go to http://garmin.openstreetmap.nl/. This is a dedicated site to allow you to get the maps you need, and it’s free!

UPDATE: openstreetmap currently only allows entire countries. For more flexibility try https://extract.bbbike.org/

Second, and an important step, is to set the map to the bike maps. It’s the first option on the site:

If you’re wondering, ‘fiets’ is Dutch for ‘bike’.
If you miss this step, the map you get will not be completely useless, but the bike only maps are actually smaller, so you can fit more on and have the information not to send you on a highway.

The next step is to move to the area that you want to have on your Edge 520. You can select an entire country, but it’s likely that the map is too big to fit on the internal storage of the 520 (you only have about 100Mb of storage). As you can see the maps is cut up in tiles.

After you found the area you’re interested in, you need to enable the ‘manual selection’ just above the map:

Now you can select tiles on the map by clicking on them. While doing so, keep an eye on the side bar, it will give an estimation of the map size, which you want to keep under 90Mb. You can fit more (about 100Mb), but you need to keep some space for your session, strava and other files. If you keep it to 90Mb you have a large safety margin as the Garmin and Strava files are pretty tiny.

Once you’re happy with your selection, fill in your e-mail address and add your map request to the queue.

The site’s servers will generate a seamless stitched together map of your selection. This may take some time depending on the demand.

Installing the Map on your Edge 520

Once it’s ready you’ll receive an email. Follow the link in the e-mail and you’ll be presented with a couple of downloads:

The one you want is ‘openfietsmap_lite_gmapsupp.zip’. The one just above the license.txt. The other files are there in case you want to use it on other platforms, so you can ignore them. After your download is completed you can go and unzip the ‘openfietsmap_lite_gmapsupp.zip’ file.
In the zip folder you’ll find a file called gmapsupp.img (it may not display the file extension on your machine).

This is the file you will copy to your Garmin Edge 520. So now you’ve got it, go ahead and plug in your Edge 520 using the USB cable and wait for it to be mounted as an external drive. I’m on a mac but the process is exactly the same on a windows machine.On the Edge 520 you will see a folder called Garmin and within it you’ll see ‘gmapbmap.img’, again with or without the extension. This is about 45MB and is the file we are going to overwrite. First, make a local copy of it and keep it somewhere safe for backup purposes.

Then let’s go back to the downloaded file and rename the downloaded ‘gmapsupp’ to ‘gmapbmap’ (keep the .img extension if you see it). Here I’ve copied the original Garmin Base Map to the same folder and renamed it to _backup. I’m renaming the downloaded map to ‘gmapbmap’.

Now you’re ready to copy the new map on your Garmin Edge 520. Copy it over into the Garmin folder and give the ‘overwrite’ question a ‘yes’. If you don’t get this prompt, you are either in the wrong folder or have the filename wrong and it will not work. Make sure the new file’s name is exactly as you see the old one.
Wait for the copy to finish. If you’ve chosen to delete the original and then copy the new map, you may need to empty the trash to actually clear out the space needed for the new map.

Then, when everything is done, safely eject the Garmin 520. (right mouse click on the Garmin -> eject). You need to do a safe eject to make sure the file transfer is completed. This was the last step, now you can unplug your Garmin and boot it up. It will load the new map, which you can see in the boot up text, as shown below, (this may take a second but is pretty fast) and you’re good to go!

To actually see the map, you need to make sure the GPS signal is good and your location is within the map you created. Otherwise you’ll just get an empty map screen. If you are sure you did it correctly, but still have a blank map, Graham found the problem:

In case anyone else had the problem where after copying gmapbmap.img, the map display was blank. And even copying the original file, the map is blank… Oh no!
The problem in my case was that the files originated from an encrypted Windows folder. Copying the files to the Garmin did not remove the encryption. The solution was to remove the encryption first on Windows (right-click, Properties, Advanced, Uncheck: Encrypt contents…), then copy the files to the Garmin.
Phew!

If you have any questions or are stuck in the process, drop a comment below or contact me on Facebook, Twitter or Instagram. I’m happy to help out! If you like this post and found it helpful, please support me by shopping at my sponsors using the banners on the side or go directly to Amazon or Wiggle via these links!

The Open Street Maps is an open source project, maintained by volunteers who spend their time improving the maps and adding information. You can help by making donations or adding information yourself! Hosting of the Garmin OpenStreetMap is sponsored by Oxilion and others. Slippy map and Garmin maps are based on OpenStreetMap data.

P.S. Your Garmin 520 will function without a map file.

P.P.S. If you get an error when you want to install a device update, that there’s not enough space just temporarily remove the map file and put it back after the update.