shonkymaps.img – Use this if you simply want a file to copy into the /Garmin directory on your garmin / navigator device or SD card. This file contains the large-scale and full topo minus contours, this is the most popular set.
Please Note: Some Garmin devices sold prior to around 2012 require the copied file to be named gmapsupp.img. If you need to rename the file after you download it be careful not to overwrite any existing file of the same name as it may contain other maps that you don't want to lose – if this is the case you will need to download and install shonkymaps using MapSource or Basecamp
shonkymaps_3.51.zip – Use this to install shonkymaps into Mapsource or Basecamp on your windows PC. This contains an installer that will install the full set of shonkymaps, including full topo (including 50m contours), Large Scale, A set of full topo without contours, and finally a transparent contour set. You can then use Mapsource or Basecamp to select and install the tiles you need.
Click here for Mac-specific instructions
If you are a linux user or want the small IMG files without a Mapsource installer, then this is for you.