Galleries must showcase more than a few artists to be considered. The site should have the look and feel of a thoughtfully created online gallery with current and fresh art work for sale, preferably with a physical location (though, this is not necessary). Galleries with only a few art pieces by a couple of artists--this may qualify it for "Artists" category not "Galleries."
Nicely arranged galleries showcasing outsider artists from around the world. Outsider artists are self-taught artists whose art work clearly has an unrestricted feel; mainstream artistic boundaries are crossed. Generally, more sophisticated than southern folk art and created by people from all walks of life and regions of the world, not just the southern/southeastern parts of the United States.