Mapdex is an extensive database portal searchable by spatial layers, fields,
and map service names. The site has approximately 1,715 servers, serving
approximately 30,000 map services, and containing approximately 475,000 GIS
layers. It brings together a previously disparate network of GIS services,
searchable from one location, that can be tapped into by the GIS community
using just a few keyword searches and mouse clicks. Users can also learn about
its origin, date of creation, scale, and a myriad of metadata variables.