Situated in the Primavera Sierra, 20 km (12 mi) west of Guadalajara along the Guadalajara-Tepic Highway. It is considered the most important national park in the metropolitan area and acts as the cityâ€™s lungs. It has a territorial extension of 36,229 hectares (89,485 acres), full of pines and Encino oaks. Inside the park you can see what was once the Colli Volcano. In this forested area youâ€™ll find several mountain-biking routes, such as la Mosca, an exhilarating 25-km (15-mi) path that takes you between trees, around sharp turns and down steep trails. The Toboganes path is a meandering 35-km (22-mi) trail through the forest. Other trails include the Obisidianas, which leads cyclists to the springs of Rio Caliente – a boiling hot river, and the Tronadora, which runs along part of the Vigia 1 path in the El Centinela Forest.