Puerto Rico, officially the Commonwealth of Puerto Rico, is a Caribbean island and unincorporated territory of the United States. It is located in the northeast Caribbean Sea, approximately 1,000 miles southeast of Miami, Florida, between the Dominican Republic and the U.S. Virgin Islands, and includes the eponymous main island and several smaller islands, such as Mona, Culebra, and Vieques. It has roughly 3.2 million residents, and its capital and most populous city is San Juan. Spanish and English are the official languages of the executive branch of government, though Spanish predominates. Puerto Rico was first settled by a succession of indigenous peoples beginning 2,000 to 4,000 years ago; these included the Ortoiroid, Saladoid, and Taíno. It was then colonized by Spain following the arrival of Christopher Columbus in 1493. Puerto Rico was contested by other European powers, but remained a Spanish possession for the next four centuries.