The article deals with electronic availability of the biggest Czech digitized map collections. The technical requirements for the equipment of a user were examined, as well as the possibilities and difficulties of search, types, quality and metadata standards, the attributes of displayed information and other services with images such as zoomify, files downloading or printing.
Overall comfortableness of the work with the portal or the availability of help were evaluated. The attention was also paid to compliance with copyright, licence and organizing rights.
Some portals make available also statistics of access and use. Added services mostly include geographical search with the use of spatial data, the possibilities to georeference maps, overlap layers and compare the works.