Colmenar del Arroyo and Sevilla la Nueva Bunkers Loop

This is a challenging route that generally takes around 5 hours and 11 minutes to complete. However, given its difficulty and varied terrain, it's wise to plan for potentially longer, especially if you stop to explore the historical sites.

The route features a highly varied and often demanding terrain. You'll encounter approximately 25.1 km of loose ground and 23.4 km of natural or unpaved paths. There are also about 6.30 km of paved sections and 883 meters of singletrack, requiring advanced riding skills and good bike handling.

The route is rich in historical and scenic points of interest. You'll have the opportunity to visit several Spanish Civil War bunkers, including the well-preserved Spanish Civil War Bunkers near Colmenar del Arroyo and specifically Bunker 13. Additionally, you can enjoy views from the Viewpoint of Cabeza Gordo and Peña de Cenicientos and cross the Bridge Over the Perales River.

No, this route is classified as a 'difficult' mountain bike ride. It requires very good fitness and advanced riding skills. Some sections may even necessitate pushing your bike. It is not recommended for beginners or families with young children.

To avoid extreme temperatures, the best times to ride this route are typically spring (April-May) and autumn (September-October). Summers can be very hot, and winters can bring cold and potentially wet conditions, making the already challenging terrain more difficult.

As a circular route starting and ending in Sevilla la Nueva, you can typically find parking within the town itself. Alternatively, if you prefer to start closer to the bunkers, parking options may be available in Colmenar del Arroyo.

While dogs are generally allowed on public trails in Spain, it's always best to keep them on a leash, especially given the length and difficulty of this route, as well as the presence of varied terrain and potential wildlife. Ensure your dog is fit enough for a long, challenging ride.

Generally, no special permits are required for mountain biking on public trails in this region of Madrid. However, always respect local regulations and private property signs you might encounter along the way.

Yes, the route intersects with several other paths. Notable sections include parts of the Ruta Verde 5.7 Móstoles - Sevilla la Nueva, Camino Viejo de Navalcarnero, Camino de las Labores, and the Cañada Real Leonesa, among others.

Given the route's difficulty and length, you should bring ample water, energy snacks, a repair kit for your bike, a first-aid kit, and appropriate clothing for the weather. A GPS device or the Komoot app is highly recommended for navigation.

This is a largely natural and rural route, so dedicated facilities like restrooms or official water sources are scarce. It's crucial to carry enough water for the entire duration of your ride. You might find amenities in the towns of Sevilla la Nueva and Colmenar del Arroyo at the start or end of your journey.