Isla Culebra is an island, town and municipality of Puerto Rico, and together with Vieques, it is geographically part of the Spanish Virgin Islands. It is located approximately 17 miles east of the Puerto Rican mainland, 12 miles west of St. Thomas and 9 miles north of Vieques. Culebra is spread over 5 barrios and Culebra Pueblo, the main town …Isla Culebra is an island, town and municipality of Puerto Rico, and together with Vieques, it is geographically part of the Spanish Virgin Islands. It is located approximately 17 miles east of the Puerto Rican mainland, 12 miles west of St. Thomas and 9 miles north of Vieques. Culebra is spread over 5 barrios and Culebra Pueblo, the main town and the administrative center of the island. Residents of the island are known as culebrenses. With a population of 1,792 as of the 2020 Census, it is Puerto Rico's least populous municipality.