A solar collector for heating a gaseous heat transport medium comprises an open-top housing provided with a transparent cover layer formed of a plurality of adjacently arranged, substantially mutually contacting, sealed and evacuated transparent cover tubes. The inner surface of each cover tube is provided with a selective absorption layer over the half facing the interior of the housing. The surface of the housing bottom facing the cover tubes has a vaulted profile corresponding to the shape of the cover tubes. An inlet and an outlet are respectively provided in the opposite sidewalls of the housing for flow of the gaseous heat transport medium transversely of the cover tubes in direct thermal contact herewith.