Marchena Island (Spanish: Isla Marchena) is one of the Galapagos Islands in Ecuador. It has an area of 130 square kilometers (50 sq mi) and reaches an elevation of 343 meters (1,125 ft) above sea level. The island does not receive visitors, although the surrounding water is used by aquatic divers on organized tours. People generally see the island as they sail around the northern part of Isabela on the way to Genovesa Island.[citation needed]
Marchena has an area of 130 square kilometers (50 sq mi) and reaches an elevation of 343 meters (1,125 ft) above sea level.[4] Marchena's nearest neighbor is Genovesa Island, about 72 kilometers (45 mi) due west.[citation needed]
Like many of the Galápagos volcanos, Marchena has a caldera.[citation needed] Marchena's caldera is roughly elliptical and measures 7 by 6 kilometers (4 by 4 miles), within the range of caldera sizes of the large western volcanoes.[citation needed] Marchena's caldera is unusual, however, in that it has been almost completely filled with young lavas, some of which has spilled over and down the sides.[citation needed] The oldest lava pools go back 500,000 years.[citation needed]