Those mountains are in the Weminuche Wilderness
At 488,210 acres, the Weminuche Wilderness is the largest wilderness area in Colorado. The average elevation on the Wilderness is 10,000', but there are 3-14er's here (Windom, Eolus and Sunlight Peaks) and many others that pass 13,000'. But climbing the high peaks in these mountains is different: nearly everything is volcanic in nature and a lot of it is "rotten" with loose and crumbling rock. That same volcanic rock makes for rich, fertile soil and grows a pretty heavy forest cover, too.
There are many established trails (more than 475 miles worth) in the Weminuche Wilderness, including a 50-mile section of the Continental Divide National Scenic Trail. The wilderness is split between the San Juan and Rio Grande National Forests, the dividing line being the Continental Divide.
The Weminuche Wilderness contains the headwaters of the Rio Grande and San Juan Rivers. This is a massively glacier-carved region in a mountain range that was formed by long-term volcanic activity 60-some million years ago. There are hot springs in some areas but what you'll find most often are the ruins of old mine sites. Because of the size of the property, the number and heights of the mountains, the various recreational opportunities and the relative ease of access, the Weminuche Wilderness is more heavily impacted by human use and abuse than any other wilderness in Colorado.
The San Juan Mountains in Weminuche Wilderness
The Needles, in the western reaches of Weminuche Wilderness
Wilderness Areas in the San Juan Mountains
Mt. Sneffels Wilderness - Lizard Head Wilderness
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