Tinian is one of the three principal islands of the Commonwealth of the Northern Mariana Islands. Tinian is about 5 miles (8 km) southwest of its sister island, Saipan, from which it is separated by the Saipan Channel. It has a land area of 39 sq.mi. (101.01 km²). Together with uninhabited neighboring Aguijan Island (2.74 sq mi, or 7.09 km²), it forms Tinian Municipality, one of the four constituent municipalities of the Northern Marianas.
The total area of the municipality is 41.74 sq mi (108.1 km²). Tinian's largest village is San Jose. The island has a variety of flora and fauna, and limestone cliffs and caves. The Tinian Monarch is the island's only endemic bird species and it is threatened by habitat loss. There is a variety of marine life and coral reefs surrounding the island. Its clear, warm waters are ideal for snorkeling, scuba diving and sport fishing.
Tinian has two gas stations and a casino. The village of San Jose has several smaller hotels and restaurants and bars. The airport is small and serviced by two airlines, Freedom Air, which operates daily scheduled flights, and Star Marianas Air, which operates by charter. The ferry boat service that operated twice daily between Tinian and Saipan ran at a loss estimated to be US$1 million a year, and has now ceased. The island has the only intact Shinto shrine on the Mariana Islands.Much of the local economy is dependent on tourism. The largest employers on the island are the government and the casino. As of March 2006, the island has plans to put in four new casinos The 2010 census showed a population of 3,136 for the island.