Granite Outcrops Along Highway 87, Black Hills National Forest

Needles Highway cuts through granite spires in Custer State Park, part of South Dakota's Black Hills. The road was completed in 1922 under the direction of Governor Peter Norbeck, who laid out its route on foot and horseback to highlight the granite formations rather than avoid them. The rock towers here are remnants of an ancient batholith, exposed over millions of years as softer surrounding rock eroded away. Ponderosa pine forest covers much of the surrounding terrain, with stands thinned in places by wildfire and beetle kill common to the Black Hills. Custer State Park itself covers more than 71,000 acres and adjoins Wind Cave National Park and the Black Hills National Forest to the south.