Alquézar is a municipality in the province of Huesca, in the autonomous community of Aragon, Spain. As of 2012, its population was 301. Situated on a limestone outcrop of the Eocene age to the west of the canyon of the Rio Vero in the Sierra y Cañones de Guara Natural Park, the village grew up around a castle and the Collegiate church of Santa Maria, which was consecrated in 1099.