RIPLEY (AP) — With its legacy as a haven on the road to freedom for hundreds of runaway slaves, the hilltop home of the Rev. John Rankin and its contents attract continued interest from historians and tourists.

Visitors enter the pre-Civil War era when they step into the simple two-story house, built by Rankin in 1829 in Ripley, about 50 miles upriver from Cincinnati.

They can observe the period furnishings and some of Rankin’s possessions, including the Rankin family’s Bible, his eyeglasses, the first-edition copy of Rankin’s 1826 anti-slavery book and part of a letter he wrote.

They can look out the front windows, where lit candles guided fugitive slaves from the Kentucky side of the Ohio River.

They can walk down and back up the reconstructed 156-step stairway the fugitive slaves climbed to get from the Ohio River to Rankin’s house.

For the last several weeks, interest has shifted to what’s beneath the Rankin site.

Archa eologists hired by the Ohio Historical Society are painstakingly digging an area beside the house to see if they can find anything of historic value.

Because the Rankin site is a National Historic Landmark, the state had to conduct the archaeological dig before placing an underground heating and air-conditioning unit next to the house. The unit is needed to protect the house and its artifacts from excessive heat and cold, said Kim Schuette, Ohio Historical Society spokeswoman.

“Everyone in the community is excited about the excavation,” said Betty Campbell, site manager for the Rankin House State Memorial. “We’re definitely going to learn more about what took place here.”

She works for Ripley Heritage Inc., which manages the site for the Ohio Historical Society. The state has owned the site since 1938. So far, the dig has uncovered a pit cellar, where people stored vegetables; evidence of a possible horse corral; the foundation of a summer kitchen; and the top of a prehistoric earth oven.

Their discoveries include shards of stoneware from jugs and pots, a horse’s skull, dozens of nails, a slate pencil, a projectile point dating to around 700 A.D. and an 1883 Indian Head penny.

“They’re all little pieces of a puzzle,” said Bill Pickard, assistant curator of archaeology with the Ohio Historical Society. “It might turn out that 90 percent of it doesn’t relate to the Rankin era.”

The state is paying Ohio Valley Archaeology Inc., a Columbus firm, $16,905 for the excavation, with a contingency for $9,000 more if additional excavation is needed.

Albert Pecora, vice president of Ohio Valley Archaeology, and Jeff Dilyard, a staff archaeologist, have been using shovels, small scoopers, brushes and sifting pans to find historic artifacts.

Before the digging began, the site was surveyed with ground-penetrating radar.

Rankin’s home, which saw 5,709 visitors last year, was one of southern Ohio’s most impo rtant stations on the underground railroad, and Rankin himself was a leading abolitionist.

Born in Tennessee in 1793, Rankin moved from Kentucky to Ripley in 1822. A Presbyterian minister and educator as well as a farmer, Rankin built his hilltop house seven years later.

From 1829-63, more than 2,000 runaway slaves found shelter in the Rankin house. They were hidden in the cellar, which now is accessible to visitors, and in the attic, which is off limits.

Rankin also hid slaves in a cellar beneath his barn.

Campbell said no one knows the location of the barn. Rankin hid as many as 12 fugitive slaves at one time.

Rankin left Ripley in 1863, after President Lincoln’s Emancipation Proclamation.

“He felt he had done all he could for the cause,” Campbell said.

Rankin died in Ironton in 1886.

The archaeological excavation would have ended about three weeks ago if the dig hadn’t uncovered the pit cellar and the horse corral.

“T his place had multiple buildings for many uses, and every building had a cellar,” Pecora said.

Excavation will continue in an effort to complete the house renovations; however, the Historical Society cannot do further exploratory archaeology due to lack of funds, Schuette said. If funding becomes available, the society will be able to explore further in the future.

“You never know,” Campbell said, “what the next shovelful of dirt might reveal.”