Serra da Enciña da Lastra Natural Park, Nature park in Rubiá, Spain

Serra da Enciña da Lastra is a nature park built on limestone terrain with steep valleys and high cliffs, while the river Sil cuts through its eastern side. The landscape combines different elevations and rock formations shaped over geological time.

The park was declared a natural park in 2002 by the Junta de Galicia, covering 3,151.67 hectares in the municipality of Rubiá, Valdeorras. Its limestone belongs to the Aquiana limestone, a reef formation with fossils of bryozoans and other Ordovician organisms from when the area lay under the sea. The Instituto Geológico y Minero de España included part of the area in the geological interest point "Minas de Pintura" (PIG OR-3), which takes in a pre-Silurian limonite deposit at Pardollán, the Covas strait and the Penarrubia limestone massif.

The name Enciña da Lastra refers to the ridge itself, and the caves here are called palas in local speech. The village of Covas, at the narrow gorge of the same name, gives its name to the park's best-known limestone passage. Chestnut woods and grazing on the valley floors mark centuries of rural use.

A visitor center in Biobra provides information about trails of different difficulty levels and details on local geology and nature. Visitors should prepare for changing conditions and bring suitable footwear for uneven ground.

The park holds the largest cave and chasm network in Galicia, with notable caves near Covas and Biobra. Its limestone also preserves Ordovician bryozoan fossils from when the area lay under the sea, and part of it is included in the geological interest point "Minas de Pintura" (PIG OR-3).