Geologic age: Cambrian

The distance is 2.2 miles to the Deadwood Sandstone. Continue north for 1.7 miles on route 385 to the junction of route 87. Turn right and drive 0.5 miles. Look for a large basin on the left side of the road. Much of the Deadwood Sandstone is on the north end and at the bottom of the basin.

Sandstone is sedimentary rock composed mostly of grains of quartz that vary in size. The Deadwood Sandstone is brown to light gray in color.

In what types of environments does sand accumulate?