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The Isthmus of Catalina Island is a 770-meter (842 yards) section of land that joins the northwestern portion of Santa Catalina Island to the main part of the island. It lies approximately 37 km (23 mi) southwest of San Pedro Harbor. Part of the isthmus is occupied by the town of Two Harbors, named for two harbors on either side of the isthmus, Isthmus Cove and Catalina Harbor. Two Harbors lies on the leeward side facing Isthmus Cove. The northern part of Santa Catalina contains about one-sixth (31.7 km) of the entire island's land mass.