One of our favorite activities in the Black Hills of South Dakota is to visit Wind Cave National Park. I love the unique engineering design in the pigtail bridge used in place of an insanely impossible hair pin turn to navigate down the side of a ravine.

We are camped near Custer State Park and the town of Custer in the southern part of the Black Hills at Custer's Gulch RV-Park. It is an OK commercial campground just like dozens of others in this area.

One lane bridge in Wind Cave National Park western South Dakota

This one lane bridge is in Wind Cave National Park located a bit south of Custer State Park and the city of Custer.

Pigtail Bridge warning sign from Wind Cave National Park located in western South Dakota

This is one of the pigtail bridge signs, it is a good indication things are going to happen fast.

One lane bridge sign from Wind Cave National Park located in western South Dakota

You don't see signs like this if you are from east of the big river. In this case the other direction has the right of way while traffic headed in this direction must wait to enter the one lane bridge. I wonder why it is not a 2-way stop taking turns but that is not the way it is set up.

Pigtail Bridge in Wind Cave National Park located in western South Dakota

By now pigtail bridges are becoming as common as flies around a feed lot. Not really but there are a number of these engineering marvels located throughout the Black Hills. I think this one is located in Wind Cave National Park south of Custer and north of Hot Springs.

Pigtail Bridge in the Black Hills of South Dakota

If you are not familiar with pigtail bridges they are a road construction technique where a road bridge loops over its own road, allowing the road to climb rapidly. Another name might be spiral bridge. This technique takes the place of hairpin turns and is useful in steep terrain, or where the approach road to a bridge would terminate too far from the bridge's end.

Click here for more pigtail bridges in the Black Hills.

That is all there is.