Volcán Bárcena, formed by eruptions during 1952-53, is the most prominent feature of Isla San Benedicto, the NE-most of the Revillagigedo Islands, 350 km south of the tip of Baja California. San Benedicto island, elongated in a NE-SW direction, contains a series of Pleistocene trachytic lava domes at the north end. The southern end of the 4.5-km-long island is formed by Bárcena and Montículo Cinerítico, a smaller tephra cone that preceded and was largely overtopped by Bárcena. Montículo Cinerítico may also have been constructed during the past few hundred years and formed the high point of the island prior to the formation of Bárcena. Growth of the 300-m-high Bárcena tephra cone beginning in August 1952 was accompanied by strong explosive eruptions and pyroclastic flows. The eruption concluded the following year with the emplacement of two small lava domes in the crater and extrusion of a prominent coastal lava delta at the SE base of the cone.