This is a BLM trail park for mountain biking called Rock Quarry. It’s north of Alamosa just south of Del Norte. As you can see, in the middle of this area is an abandoned rock quarry. Not sure how or what was being ‘mined’ but there is a rather unusual hole in the ground where people cannot get in or out. Terrain in the area is yes, very rocky and riding trails were technical but very scenic. I was surprised how far I was able to progress through this without scrapes. Too a break and later visited under cloudy skies a large loop just in town at Del Norte CO.
