The spectacular Iron Mountain Road in the Black Hills of South Dakota

Traveling the Iron Mountain Road in the Black Hills of South Dakota, also known as US high-way16A, is an unforgettable experience. It surely is the most unusual and captivating road in America that will leave the traveler spellbound.

The road is only 17 miles long but with the many switchbacks, including what some have said is the only double spiral in the world. It will take 45 minutes to navigate the 314 curves, 14 switchbacks, 3 tunnels and 3 pigtail wooden bridges and turns that loop over their own road, allowing the road to climb rapidly.
A bus shown above is able to drive though the tunnels with almost no room to spare.
When traveling north from Custer State park on a clear day all three tunnels frame Mt. Rushmore National Memorial like a picture frame.

Occasionally traffic is stopped to wait for a buffalo herd slowly crossing the road.