The Iron Mountain Road near Custer, South Dakota is a memorable and incredible journey for anyone who ventures down it. Known also as 16A, this road is considered by many to be one of the country’s most captivating and unusual roads. With the natural beauty of the valleys and the mountains as the backdrop, the Iron Mountain Road was designed specifically to include a large number of curves, or switchback, that result in the speed of cars being limited to thirty-five in order for travelers to be able to take in the beautiful Black Hills National Forest region.

US 16 near Keystone, SD

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