Orsara Bormida borders the following municipalities: Montaldo Bormida, Morsasco, Rivalta Bormida, Strevi, and Trisobbio. It lies in a territory which was occupied by a forest; only from the 13th century agriculture took possession of the area. It was a fief of the Malaspina family until 1530. It is home to a castle, built in the 11th century.