ULYSSES — A working ranch in northwest Kansas that contains historically significant chalk formations that are among the Eight Wonders of Kansas, as well as 12,000 acres of mineral rights, is up for auction.

Monument Rocks, also known as the Chalk Pyramids, is part of an auction for the Pyramid Ranch in Gove County, which began last week and continues through Aug. 14, The Hutchinson News reported Tuesday.

The formations are part of ancient chalk beds that were carved into unusual shapes when the central U.S. was covered by water. The 50-foot-spires of Monument Rocks, also known as the Chalk Pyramids, are a National Natural Landmark. The formations were an important landmark for stagecoaches on the Butterfield Overland Dispatch Trail and Fort Monument, a post-Civil War fort that was established in 1865 to protect the stagecoach and mail route.

The 13,000-acre Pyramid Ranch also includes fossil finds, two graves of U.S. Cavalry soldiers and was a territorial marker and spiritual site for Native Americans, said Chris Faulkner, a broker with Faulkner Real Estate of Ulysses, which is conducting the auction.

The buyer will purchase all outstanding shares of Thies Pyramid Corp., which currently owns the working cattle ranch, Faulkner said.

“The only thing (the corporation) owns is the ranch,” Faulkner said. Selling the shares is a way to reduce taxes.

Faulkner said he couldn’t determine the value of the acreage because of its history and mineral rights. Grass pasture in western Kansas can bring up to $600 an acre, he said.

“We have been selling agricultural property for almost 30 years,” he said. “We do a lot of land auctions. But we have never sold anything quite like this.”

Anyone can place a bid through 5:30 p.m. Aug. 14 by calling (620) 356-5808. Bidders will be notified of the current bid when a higher bid is received. No bids were received the first week of marketing the property, Faulkner said.

Although it is on private property, the public has been allowed on the site to view the formations.

Barbara Shelton, a partner in the Keystone Gallery on the Scott/Logan county line not far from Monument Rocks, said she regularly sees visitors from the site.

“I guess we’ll see who buys it and what they do,” she said. “It’ll be their property to do with what they wish.”

Faulkner said there are no provisions for continuing the public access.

“This would strictly be the new owners’ call, but I would hope they would continue the legacy of this fine property,” he said.

Marci Penner, director of the Kansas Sampler Foundation, which named the Eight Wonders of Kansas, said some of the formations on the site have begun to crumble but she hopes the new owner will allow the public to continue visiting.

“When you first see it, your jaw drops,” Penner said. “It is this tall, chalk sentinel out there on the flat prairie. It is so unusual to see it.”