The Fossil Forest Trail is a 3-kilometer circular interpretive hiking trail that crosses the Castillería Valley in the Palentina Mountains (Palencia, Castile and León). The main point of interest is a vertical rock face approximately 150 meters long and 18 meters high, exposed by former open-pit coal mining operations. On this wall, visitors can clearly see the contours of stumps, trunks, and root marks from a forest of lycophytes and Cordaites that thrived in a coastal area during the Carboniferous Period, more than 300 million years ago. The forest was destroyed by a tsunami, which allowed it to become fossilized in the rock. From the visitor center, visitors can admire the site from a viewing platform equipped with interpretive panels that help explain the area’s geology. The trail winds through a dense oak forest before reaching the site and also offers other attractions such as the Peña Celada overlook and, a few meters further on, the La Pernía viewpoint, which provides an exceptional panoramic view of the region with peaks such as Curavacas and the Picos de Europa in the background. The route is well-marked and easy, suitable for all types of hikers. The site is protected as a natural monument and is considered one of the most important preserved coastal fossil forests in Spain. The area is home to a rich variety of wildlife, including brown bears, red deer, roe deer, wild boars, common buzzards, goshawks, salamanders, and other amphibians and reptiles. The best time to visit is in the fall, when temperatures are pleasant and the landscape transforms into a mosaic of colors, although the trail is recommended year-round.
