Hidden near a small neighborhood on the city's west side, the Native American landmark has quietly attracted archeologists and historians. Now, several residents are determined to restore the preservation, repairing years of wear and tear that's eroded its natural beauty—but not its mystery.

Effigy mounds created by Native American tribes more than a thousand years ago are prominent throughout southern Wisconsin. Some are polished and flawless, while others have deteriorated.

Mounds in the Whitewater preservation are void of significant damage and are marked with signs to describe what visitors are seeing. But invasive plants have sprawled throughout the site, and some residents have used the park to walk their dogs, which is prohibited.

"Whitewater is one of the best-preserved in that part of the state," said archeologist Robert Birmingham, who has authored books about effigy mounds in Wisconsin. "(They) really are an archeological world wonder."

Birmingham estimates Whitewater's mounds were built between 700 and 1100 A.D. Among them are thunderbirds, "panther-like water sprits," snakes and a mink.

He said almost all sites were built near natural springs, a representation of life.

"Springs were considered entrances into the spiritual world," Birmingham described in the restoration plan. "It is life itself coming up. About 1,000 years ago, this was considered to be a very special spot, even before the mounds were built, because of the springs to the north of the site."

Birmingham noted that the oak savanna makes the site more special, calling it "very rare."

Whitewater's site might have a feature even more significant. Matt Amundson, parks and recreation director, said there could be an intaglio at the west end of the preservation. Intaglios are depressions in the ground rather than mounds.

The only known intaglio in the world is in Fort Atkinson. Whitewater would need experts to confirm whether the low spot is an intaglio before declaring it as such.

At least two groups—Friends of the Mounds and the Whitewater Landmarks Commission—are dedicated to restoring and preserving the mounds.

Mariann Scott, chairwoman of the landmarks commission, said people in the city for many years weren't clear on how to oversee the mounds, but that's changing.

"I was familiar with the mounds, but it was not a place I went to frequently," Scott said.

She and other members started attending conferences and workshops to learn more about their role on the commission. State regulations protect effigy mounds under its "burial law," treating them as graves.

Work to improve the site started in late 2010 with a 20-page preservation and maintenance plan. The draft describes everything from restoring the mounds and planting trees to protecting the oak savanna.

Volunteers and city staff in early April cleared brush and fallen branches. On April 25, they burned off invasive species, making room for natural vegetation.

Most effigy mounds are burial sites, but Birmingham said it hasn't been determined whether Whitewater is one of those locations.

The soil, all 20 acres in Whitewater's preserve, is protected as an archeological site. That prevents people from planting trees without special permission, Scott said.

"We're had to learn this bit by bit ourselves," she said.

Because the site is protected, a 5-foot buffer separates it from neighboring homes, which are just a few yards from the mounds.

During an early visit to the site, she said they discovered someone had built a fence on the preserve, as if to include it within their property.

None of the neighbors responded to Gazette requests for interviews.

Scott said some neighbors seem confused about the boundaries. To remove the fence, she said, one expert suggested cutting it off at the base and leaving the post stumps in the ground to avoid further damage to the site.

The commission and other city officials have yet to approve the restoration plan, which still is in draft form.

State historian Rob Nurre is hoping they'll consider a few changes. He believes the current master plan focuses too narrowly on protection of the oak savanna.

While he agrees protection of the vegetation is an important element, he wants to see more details about how the mounds would be preserved.

Nurre is a caretaker for the historic "man mound" in Baraboo—one of few known mounds that appears to depict a human. Early spring is the best time of year to visit the mounds because the vegetation has not yet grown, making the mounds' forms more obvious.

"My concern is if the city is going to develop a more complete plan for the site, including trails and how visitors interact with that site, I'd like to see a lot more thought put into the archeological resources that are there," said Nurre, who also is the archeological sites chairman for the Sauk County Historical Society and preservation of sites chairman for the Wisconsin Archeological Society.

The landmarks commission planned to consider Nurre's input this month.

It's a strong start, but the commission and other community volunteers still have a ways to go, Scott said. She'd like the see the preserve used for multiple purposes, including biology or ecological education.

The city already indicated it would like to include signs to educate visitors, and a new sign will be placed at the roadside to mark the preserve's location.

"Our goal is historic preservation and restoration," Scott said. "It's public land, and it's supposed to be available to the city and people who want to see it. It's really a very educational site … the more you know the more you see when you're out there."