Fort Colcura, Spanish colonial fort in Lota, Chile

Fort Colcura is a fortification on a hilltop overlooking Arauco Bay in the Lota region and provides strategic command over the Colcura valley below. The structure incorporates natural cliff defenses and displays a curved outer wall on the accessible side facing the main approach.

A small fort existed here from the start of the conquest, destroyed and repaired repeatedly by the Moluches. After the Mapuche uprising of 1598, governor Alonso de Ribera rebuilt it in 1602 as San Miguel Arcángel. Following the 1655 insurrection, Pedro Porter Casanate raised a new fortress on the old foundations in February 1662; he died there on 27 February 1662.

The fort's name, San Miguel Arcángel de Colcura, comes from the 1662 fortress built by governor Pedro Porter Casanate on the old foundations. Porter Casanate died there on 27 February of that same year. The site later gave its name to the Playa de San Miguel Arcángel de Peredo, founded by his successor Ángel de Peredo, which in time became known as Colcura.

Access is free and public, by dirt footpaths and vehicle tracks climbing from both Colcura and Lota. The cannons on the point are period pieces mounted on modern metal, and a small pool stands on the site. The position is an exposed lookout over the Gulf of Arauco, so expect wind and mud after rain.

The cannons now mounted at the site are period pieces but rest on modern metal supports; they are attributed to the coastal battery installed at Punta Fuerte Viejo during the War of the Pacific (1879–1883) to defend Lota's coal port, and are described as two Armstrong guns and one Low Moor.