Altamura Island (Spanish: Isla Altamura or de Altamura) is an island of México, in the Gulf of California. It is located in the bahía de Santa María, on the west coast of the state of Sinaloa, southwest of Saliaca Island, separated by an area of shallow water. It is located 70 kilometers (43 mi) west of Culiacán. Its area is 101.17 square kilometers (39.06 sq mi), and it is approximately 40 kilometers (25 mi) long, while its width ranges from 900 meters (3,000 ft) to 3.7 kilometers (2.3 mi). It is one of the largest private islands in the world.