The Peñol de Cerquín (Latin American Spanish: [peˈɲol de seɾˈkin]): "Rock of Cerquín") was a mountaintop Lenca fortress in southern Honduras during the Contact Period (1520–1540). The Peñol de Cerquín was a key Lenca stronghold during the Great Revolt of 1537 against the Spanish conquest. The defences were formidable, and the Lenca warleader Lempira strengthened the fortifications considerably, and used it as his base of operations. The hardened veteran Spanish conquistadores considered the fortress to be as strong as anything they had seen in Europe.
The first Spanish expedition to pass the Peñol was led by Pedro de Alvarado in early 1536, but he did not attempt an assault. A few months later Alvarado sent his lieutenant Juan de Chávez against the fortress; his initial assault was defeated, and the siege that followed it faltered due to supply problems. Over the next year, Spanish expeditions in the general region were moderately successful, and the Spanish considered the area pacified. Unknown to the Spanish, Lempira had been fortifying the Peñol in secret, and he amassed a great quantity of warriors and supplies there before openly declaring war in late 1537. The Spanish captain Alonso de Cáceres laid siege to the fortress at the beginning of November. In spring of 1538, Lempira agreed to a parley with the Spanish, and was shot dead during the negotiations. The surprise Spanish assault that followed quickly overran the demoralised defenders, and the fortress fell to the European invaders.
Cerquín was the name of an ancient Lenca province, while peñol is Spanish, meaning a rocky crag, or butte.
The Peñol de Cerquín is located in the southeast of the Lempira Department of Honduras, in Central America. The site lies within the municipality of Erandique. The Peñol de Cerquín is to the south of the town, on the far side of the Sierra de las Neblinas, in the region of the hamlet of San Antonio La Mina.