Background I've been amassing a collection of old geological maps showing various areas of interest around Washington, but I've been disappointed that most of them are not georeferenced (i.e. they can't be used in a mapping app and show your current location on the map). While this is only a minor inconvenience, since I can toggle between a topo map and the geological map, I've been searching for a way to add georeferencing to existing maps. And I've found it!*   Software needed: