Points have a :type: property, you can define your own types and icons to use.

:types:
  :visit:
    :icon: /mapicons/tourism/visited.png
    :description: Visit
  :transit:
    :icon: /mapicons/transportation/airport.png
    :description: Transit
  :lived:
    :icon: /mapicons/friends-family/home-2.png
    :description: Lived
  :wishlist:
    :icon: /mapicons/tourism/notvisited.png
    :description: Wishlist
  :gallery:
    :icon: /mapicons/stores/photography.png
    :description: Gallery
    :legend: false

A number of markers in many colors and 3 sizes are included in the Gem. Additionally most of the icons from the Map Icons Collection are included and as of 1.5.0 these are used by default.

If you intend to use the KML output you should change these URLs to be full URLs to your site rather than relative. The KML file does not know where to get the files so you'll get broken images if you dont.

You can provide your own by placing them in images in your repo and linking to them here. You can use online services like Google maps markers and link directly to them. The ones provided were made using Googles chart API using this script.