Within this Recreation Management Zone are three isolated parcels of BLM managed lands which are popular for non-motorized trail activities. The Grandview and Skyline parcels are connected to each other via the Horse Gulch trail system (managed by the city of Durango). The trail system spans a large spectrum of difficulty levels and are heavily used by bikers and hikers/walkers/runners alike. The Animas City Mountain unit contains about 5 miles of trail beginning at 6700' and climbing up to 8,200 ', presenting stunning views of the Durango area and Animas River Valley. This trail system is primarily used by hikers and trail runners, but receives mountain bike use as well. The lower portion of the trail system, in and adjacent to Dalla Mountain Park (managed by the city of Durango), is popular for bouldering. For more information, please contact the Tres Rios Field Office.