El Jorullo, Cinder cone volcano in La Huacana, Mexico.

El Jorullo is a cinder cone volcano on the southwest slope of Mexico's central plateau, about 53 km southeast of Uruapan and 10 km east-northeast of La Huacana, in the Michoacán-Guanajuato volcanic field. Its crater measures roughly 400 by 500 m across and 150 m deep, and four smaller cinder cones have grown on its flanks. Its vents run northeast to southwest, and lava from them covers nine square kilometres around the volcano.

The volcano appeared suddenly in 1759 following a series of earthquakes and stayed active for around 15 years. The eruption destroyed farmland across the surrounding area and permanently changed the local landscape.

The volcano rose in farmland inhabited by Purépecha communities, and the 15-year eruption buried what had been a rich agricultural area. Alexander von Humboldt climbed El Jorullo on 19 September 1803 with Aimé Bonpland, the Basque settler Ramón Epelde and two indigenous servants whose names were not recorded; he noted their help and that the cones still smouldered, with air so hot that his face and those of his companions were burned.

The site lies southeast of Uruapan and is reachable by car, with a walk across volcanic ground leading to the crater and lake. Sturdy footwear is strongly recommended because the terrain is uneven and the elevation can make the walk tiring.

In its first six weeks, the volcano grew around 820 feet (250 meters) tall, making it one of the fastest known volcanic formations on record. Alexander von Humboldt visited in 1803 and described the site as a place where he could witness a landscape still being formed.