Iron Mountain Road

If you’ll be visiting Mount Rushmore National Memorial during your South Dakota travels, carve out some time to explore a nearby wonder: Iron Mountain Road. This nearly century-old scenic drive, part of the iconic Peter Norbeck National Scenic Byway, was described by South Dakota writer Bernie Hunhoff as “one of the most crooked 17 miles you’ll ever drive.” Its famous twists and turns reveal some of the best views of Mount Rushmore and the Black Hills that you’ll find in western South Dakota.

Buckle up to explore the history and must-see sights of this legendary road.

Twisted History: How Iron Mountain Road Came to Be

Peter Norbeck was a South Dakota senator when he scouted the path for Iron Mountain Road through the heart of the Black Hills in the early 1930s. Carving and blasting had begun on Mount Rushmore National Memorial a few years earlier, and Norbeck’s road would open up a new route and outstanding views of the granite faces that were taking shape on the adjacent mountainside.

Norbeck envisioned a road that would blend seamlessly with the rugged landscape and designed unique features to achieve this, including stone tunnels, switchbacks and spiraling “pigtail” bridges crafted from local timber. Did some people call him crazy? You bet. But the result is a marvel of both nature and engineering that stands the test of time.

The Route

Iron Mountain Road comprises US Highway 16A between Keystone and Custer State Park (17 miles total).

You can head south from Keystone in the direction of Custer, or drive north toward Mount Rushmore. The views are beautiful in either direction, and some say it’s best to explore it both ways to soak up its many splendors (and we agree).

How Long Does it Take to Drive Iron Mountain Road?

Driving Iron Mountain Road typically takes 45-60 minutes from end to end, not counting stops or the occasional buffalo crossing. Due to the narrow tunnels, twisting curves and dramatic elevation changes, speed limits range from just 15 to 25 miles per hour. This is a road where the journey is a big part of the fun, so embrace the slow and enjoy the ride as Peter Norbeck intended!

Things to See on Iron Mountain Road

Mount Rushmore National Memorial

Mount Rushmore, one of America’s most famous landmarks, sits at the northern end of the Iron Mountain Road in the town of Keystone. Sculpted by Gutzon Borglum and completed in 1941, the monument features four U.S. presidents — George Washington, Thomas Jefferson, Abraham Lincoln and Theodore Roosevelt — who symbolize the birth, growth, development and preservation of the United States. Visit to learn the incredible story of the memorial’s creation, stroll serene nature trails and delve into the area’s deep Native history.

Tunnels of Iron Mountain Road: Monumental Views

Some of the road’s most magnificent features are the three stone tunnels that perfectly frame Mount Rushmore’s faces in the distance. Passengers should keep their cameras ready, as these goosebump-inducing views of “America’s Shrine of Democracy” offer endless photo ops.

Those driving a larger vehicle, such as a van or RV, or those towing a trailer or camper, should review the dimensions of the tunnels before setting out:

• Doane Robinson Tunnel: 12' Wide / 11'4" High
• C.C. Gideon Tunnel: 13' Wide / 11' High
• Scovel Johnson Tunnel: 10'9" Wide / 11' High

If you’d like to stop and admire the views, Doane Robinson Tunnel has a small parking lot that can accommodate three to four cars. The other two tunnels have wide shoulder areas nearby where it’s OK to stop.

Iron Mountain Picnic Area

Pull off here to stretch your legs, take a bio break (there are public restrooms), enjoy a picnic and admire the Black Hills views. There are several short hikes you can take, but if you’re looking for something longer, the 2-mile Centennial Bypass Trail is an entry point to the Black Elk Wilderness, where you can connect with the 111-mile Centennial Trail.

Norbeck Overlook

Located at the summit of Iron Mountain, the Norbeck Overlook offers what many consider to be the best view of Mount Rushmore National Memorial. There’s a viewing platform with coin-operated binoculars as well as a plaque dedicated to Peter Norbeck just across the road.

Iron Mountain Road Visitor Center & Store

About midway between Mount Rushmore and Custer State Park is the Iron Mountain Road Visitor Center & Store (open mid-May through November). Fuel up with coffee drinks and made-to-order pizza, or pick up freshly baked cinnamon rolls for the road. If you’d like to take in the scenery a bit longer, book a stay at Spokane Creek Cabins & Campground.

Custer State Park

At the southern end of Iron Mountain Road is Custer State Park, and portions of the road lie within the park’s boundaries. If time allows, give yourself a full day to explore this magnificent wilderness. From Iron Mountain Road, you can enter the park and pick up another scenic route, the Wildlife Loop State Scenic Byway, to spot the many wild critters the park is known for.

More Scenery Awaits on Needles Highway

Peter Norbeck National Scenic Byway comprises two historical roads: Iron Mountain Road and Needles Highway (Highway 87). It was actually Needles Highway that Peter Norbeck built first, beginning in the early 1920s. Extremely narrow and even more rugged than Iron Mountain Road, Needles Highway showcases some of the Black Hills’ most striking scenery, including the sawtooth-like Needles ridge and the imposing Cathedral Spires. The road’s most famous feature is the Needles Eye, a tunnel through a slender granite spire that’s just wide enough for one vehicle to squeeze through.

Just 14 miles long, Needles Highway will take you roughly the same amount of time to drive as Iron Mountain Road, about 45-60 minutes without stops. (But plan on stopping. A lot.)

Whether you’re a lover of nature, history or road trips, Iron Mountain Road and the Peter Norbeck Scenic Byway promise a thrilling and awe-inspiring experience unlike any other. These carefully crafted routes allow travelers to immerse themselves in the beauty of the Black Hills, making it more than just a road, but a journey through some of America’s most iconic scenery.