Isla de Mona

Mona is the third-largest island of the Puerto Rican archipelago, after the main island of Puerto Rico and Vieques. It is the largest of three islands in the Mona Passage, a strait between the Dominican Republic and Puerto Rico, the others being Monito Island and Desecheo Island. It measures about 7 miles by 4 miles, and lies 41 mi west of Puerto Rico, of which it is administratively a part. It is one of two islands that make up the Isla de Mona e Islote Monito barrio in the municipality of Mayagüez.

The island is managed under the Mona and Monito Islands Nature Reserve. There are no native inhabitants; only rangers and biologists from Puerto Rico's Department of Natural and Environmental Resources reside on the island, to manage visitors and take part in research projects.