Herrería de Compludo, Historical finery forge and museum in Compludo, Spain.

The Herrería de Compludo is a finery forge in the Compludo valley, in Ponferrada, where two streams feeding the Meruelo meet. A hydraulic wheel drives a trip hammer whose strike rate is set by the water flow, and a second channel feeds air to the hearth through a Catalan trompe working on the Venturi principle. The present structure and workings date from the 19th century.

The forge's origin is tied to the monastery of Compludo, founded by Saint Fructuosus in the 6th century, though later studies reject a direct medieval link. The surviving structure and machinery date from the 19th century. It was declared a national monument in 1968, and the Ponferrada city council bought it in 2022, making it public property.

The forge's survival is credited to the Rojo-Lopez, Alvarez-Moran and Redondo-Moran families, named on a plaque at the site for keeping it working across generations. The water is split into two channels: one turns the wheel that drives the hammer, the other feeds air to the hearth. The Junta de Castilla y León listed it in 1968.

The location sits near Ponferrada and is accessible by car with parking available near the building. Wear sturdy shoes as the ground is uneven in some areas and certain sections may have low ceilings.

The water wheel operates on the Venturi principle where the stream flow is channeled in a specific way to generate maximum power. This refined hydraulic solution was an innovative answer to the demands of metal production at the time.