The Grand Canyon of the Black Hills isn't deep or wide or long by Grand Canyon standards. If The Grand Canyon is an eagle, the GCBH is an American Robin.
That's ok though. Nature's commoners deserve our appreciation. On an average weekday, your SDPB Outdoors Correspondent sees more click-through ads for car insurance than American Robins.
The thrush family carry the weight of the scientific name Turdus. Still they fly. Look out across a beer can strewn empty lot and Turdus migratorius is there, plucking the juiciest worm from its hole. The worm processes our discarded chicken bones and Twinkie ends. TM eats the worm, drops unexpectedly on the hood of your Malibu. Rain washes the white blotch down the storm drain and into the creek. The nitrogen-heavy sediment washes up on the creek bed and feeds the corn that becomes Twinkies and chicken feed.
The American Robin is a blight recycler, canceling the dull thrum of a UPS truck or an ice machine with its warbled soprano. That's not upper case Grand Staircase-Escalante, Grand Canyon Grand. Just grand maybe. People inhabit scenes. We live inside our field of vision, which is increasingly disconnected from the spaces we physically occupy. Nature is the Beyoncé of optical experience. American Robins upgrade you. They recalibrate your field of vision with the larger physical world.
The Grand Canyon of the Black Hills does not have an Eagle Rock. The rock formations of the lower-lying limestone plateau of the outer Black Hills' are more robinesque. The canyon walls were carved with a duller knife than the Colorado River, but they're also a shorter trip from Rapid City or Spearfish, and you can tour them via Grand Canyon Road, in a 4WD (recommended).
Last year the Rocky Mountain Elk Foundation and Wyoming Office of State Lands partnered to purchase 4,350 acres of land, contiguous to the Black Hills National Forest, along the route — opening it up to the public. Yes, visiting the site does involve the always dicey proposition of leaving, however temporarily, the state of South Dakota.
One reason for contemplating such an adventure is the natural bridge that awaits you. Landforms are winning geologic lotto tickets. What are the chances that wind, water, ice and time would sculpt this narrow arch into the rock? Whatever they are, like lotto winnings, the arch will disappear in a blink of geologic time, by then replaced with another, possibly in Kyrgyzstan.
To access Grand Canyon Road, exit the I-90 at Moskee Road, ten miles west of the Vore Buffalo Jump on the I-90. Take Moskee Road just shy of sixteen miles south, to the intersection with Grand Canyon Road. From there, you can take Grand Canyon Road north or south. The natural bridge is a little over five miles north. There are a couple conspicuous large boulders at roadside to mark the spot, approximately 44.39822, -104.18919.