The Cayos Arcas is a chain of three tiny sand cays and an accompanying reef system in the Gulf of Mexico. It is located approximately 130 kilometers from the mainland, west of Campeche. Their aggregate land area is 22.8 hectares. They belong to the municipality of Champotón in the state of Campeche.
The main island is Cayo del Centro, with an area of 13.7 hectares, which is scantily covered with grass. Bushes and several clumps of palms are also present. A pair of lighted range beacons stand on the cay. Cayo del Este, a cay 5.2 hectares large and 3 meters high, lies on a detached reef lying 0.5 km southeast of Cayo del Centro. Cayo del Oeste, a cay 3.9 hectares in area and 2 meters high, lies on a small detached reef about 1.3 km west of the south end of Cayo del Centro.[1][2]
The chain is uninhabited, and lacks structures except for the beacons on Cayo del Centro. Vegetation on the islands is sparse, consisting of sand shrubs and grasses. It currently serves as a navigational marker. Cayos Arcas Terminal, an extensive chain of petroleum stations on the Arcas' reef system is located to the south of the islands. The Arcas oil rigs are currently among the largest oil producers in the gulf in terms of output.
The Arcas chain was often used for military operations in the Gulf during 19th century. A naval flotilla from the Republic of Texas briefly occupied the island during action in the Republic of Yucatán rebellion. During the American Civil War the famous Confederate raider CSS Alabama used the remote chain as a rendezvous point to be resupplied while conducting operations in the gulf.