Maestrazgo (Aragonese: Mayestrato) is a comarca in southeastern Aragon, Spain. Its names derives from the Maestrat/Maestrazgo mountain massif that extends to the east to the Comarques of the Valencian Community Alt Maestrat and Baix Maestrat. The most important town is Cantavieja. It is bordered by the Aragonese comarcas of Andorra-Sierra de Arcos, Cuencas Mineras, Comunidad de Teruel and Bajo Aragón, in the north and in the west and Gúdar-Javalambre in the south, as well as with the Castellón Province (Ports (comarca), Alt Maestrat Alcalatén) in the east. Some municipal terms of this comarca are part of the historical region of Lower Aragon.