GREENWOOD – Nearly two centuries ago, wandering farm animals would likely wind up in a town pound. And their owners could get them back only if they bartered or paid the pound keeper. Almost every town had a lockup, but now very few have been identified.

In Greenwood, on the outskirts of Greenwood City, which was once the center of town, is one of the few remaining pounds. As of last month, it became the second such all-natural, stone-built pound listed on the National Register of Historic Places in the state.

It’s another feather in the cap of Greenwood’s fame, believe members of the Greenwood Historical Society, along with the ice caves that once provided the cold stuff for ice cream on the Fourth of July and the birthplace of L.L. Bean.

The pounds “were penal institutions for wayward animals,” said Christi Mitchell, architectural historian for the Maine Preservation Commission.

The only other pound in the state on the National Register is in Pownal, although Mitchell said she knows of or believes there are about 19 others scattered around the state, including in Otisfield, Jefferson, Waldoboro, Porter and Parsonsfield.

The use of pounds fell out of favor in rural communities after the Civil War and the advent of barbed wire, but surviving pounds symbolize a frontier period in the country’s history, she said.

In those olden days, animals weren’t penned in, but allowed to wander, thus the need for a pound to hold cattle, pigs, sheep or other farm animals that strayed too far or damaged another farmer’s crops. Each town had a pound keeper during the early 19th century.

“Wandering animals destroying crops was a real problem,” Mitchell said.

At a special town meeting in September 1835, Greenwood residents agreed to build the enclosure, and by May 1836 it was done, constructed from abundant New England stones.

The more or less 40- by 40-foot stonewall-type structure looked like it was an old foundation, said Kim Sparks, town manager, who was instrumental in researching and applying for the national designation.

Now, though, after a thorough cleaning out of the area that was covered with trees and grass, and a green sign signifying the site as the Greenwood Cattle Pound, 1835, everyone knows what it is.

Sparks said the historical society also did a lot of research on the pound.

“It was a group effort. We’ve known about it for a longtime,” said Sparks, who added that Selectman Wayne Hakaka had first noted that other pounds existed in the state.

“We knew it was there in the area, but we didn’t know where,” said Joyce Hathaway, a member of the historical society.

Now, the pound will be added to the historical society’s brochure and newsletter, the town’s Web site, and may grace the cover of the annual report.

A new sign will also be fashioned, showing that the pound is on the National Register.

“We’re pleased,” said historical society member John Davis. “If we find any stray cattle, we’ll use it!”