The Associated Press

ST. LOUIS — The last couple of hundred years have been cruel to Sugar Loaf Mound. Quarrying nearly destroyed it in the 1800s; construction of Interstate 55 further scarred it in the 1960s. Now, as preservationists strive to save the city’s sole surviving Indian mound, they’ve found a natural ally: the descendants of its ancient builders, the Osage tribe of Oklahoma.

Sugar Loaf, between the highway and the Mississippi River about 4 miles south of the Gateway Arch, is all that remains of a network of Indian earthworks that gave St. Louis the nickname “Mound City.” Last fall, an elderly couple who own the 900-square-foot house on top of the mound put the property up for sale. There are two other houses at the base of the mound.

Under a plan that tribal officials say has the support of Osage Chief Jim Gray, the tribe would buy the mound, demolish the homes and develop the property as an interpretive site.

The Osage Nation Congress, based in Pawhuska, Okla., adjourned Wednesday without taking up a bill that authorizes the purchase. Though lawmakers aren’t scheduled to convene again until September, Gray could call a special session as early as next month to decide whether the tribe should buy Sugar Loaf.

The Osage didn’t build Sugar Loaf, but the tribe believes its ancestors include a mound-building people that disappeared long before the arrival of Europeans in North America. That society built massive earthworks throughout the Midwest, the best-known examples being those at the Cahokia Mounds State Historic Site in Collinsville, Ill.

Andrea Hunter, the director of the tribe’s historic preservation office, said that archaeological evidence bolsters the tribe’s claim — passed on through the Osage oral tradition — that the tribe’s forefathers built the mounds. Hunter said the tribe has secured an option to buy the property, and that she’s hopeful the Osage Congress will approve the purchase.

Linda LaZelle, staff director at the Osage Nation Congress, said legislators “have been flooded with letters in support of the acquisition.” They include entreaties from archaeologists, preservationists and politicians including U.S. Rep. Russ Carnahan, D-St. Louis; St. Louis Mayor Francis Slay and south side Aldermen Kenneth Ortmann, 9th Ward, and Craig Schmid, 20th Ward.

David Fisher, the executive director of the Great Rivers Greenway District, and Laura Cohen, director of the Confluence Partnership, wrote in separate letters to the Osage Congress that the groups would like to make Sugar Loaf a centerpiece of a new riverfront trail in south St. Louis. Cohen wrote that a Mounds Heritage Trail might link Sugar Loaf to Cahokia and other Indian sites in the region.

Leigh Maibes is the real estate agent representing Walter and Eileen Strosnider, the property’s elderly owners who have moved to California to be closer to relatives. Maibes said that one potential buyer has secured an option through Aug. 5 to buy it at an agreed price, but she wouldn’t disclose the price or confirm that the Osage hold the option. She said the Strosniders will only sell to a buyer interested in preserving the mound.

Maibes said the property, at 4420 Ohio Street, is listed for $350,000 — down $50,000 from the original asking price.

The mound — but not the 1928 house on top of it — was listed in 1984 on the National Register of Historic Places.

Archaeologists have excavated little of the mound, so they’re not entirely sure how old it is. John Kelly, an archaeology professor at Washington University, has said he suspects the structure is likely a 2,000-year-old burial mound — not a signal mound, as some have suggested over the years.