Pass Creek Pass

Pass Creek Pass is a hidden gem in western Huerfano County. It crosses the Sierra Blanca ridge from Costilla County in the south to the Upper Huerfano River Valley in the north. Along the way, it passes through a simply beautiful countryside with some very interesting geology.

The mountains to the west of Pass Creek are old, about 1.7 billion years old, part of the Colorado Orogeny upthrust that put Mt. Blanca, California Peak, the Front Range, and most of the Wet Mountains in place. The mountains to the east of Pass Creek are young, about 25 million years old, all part of the igneous intrusion we call Mt. Mestas, Silver Mountain, Rough Mountain, and the Sheep Mountains. This area was once part of the Grayback Mining District, with most of the activity going on in the mountains to the west.

A drive along Pass Creek Pass is a drive along one of the fault lines that formed the Sangre de Cristo Mountains. The road crosses back and forth through upthrust plates of Dakota sandstone and in between vertical granite walls.

The vertical granite walls testify to the flow of molten magma in the cracks in the ground caused by the action along the fault line roughly 25 million years ago.