PARRISH -- Jungle long ago claimed the roofless, odd-shaped masonry building with narrow slits for windows.
It's so overgrown with vines, bushes and ferns that it could be part of a set for an Indiana Jones movie.
Even long-time Parrish residents and neighbors say they don't know when the building, located between Old Tampa Road and the Manatee River, was constructed.
Some say it's the ruins of an old post office that served the Erie farming community near Parrish.
Others speculate it was an outpost for the U.S. Army garrison at Fort Hamer during Seminole Indian War days.
Dion Schaal, 25, stumbled across the structure a year ago when he went to retrieve his dog.
The building is constructed of cinder block and concrete, and not tabby as some had suggested. Tabby was a building material made from lime, sand, water, and oyster shells that was used from colonial days into the 19th century.
Schaal was so impressed with what he saw that he reported it to members of the Parrish Arts Council.
Schaal thought that with its heavy construction, and those narrow windows, it would be a perfect place for soldiers to fire their muskets.
But Selma Sellars, whose family has lived next door to the ruin for decades, says her mother told her it was formerly the Erie Post Office, which closed in 1904.
"My mother thought it was a post office, but maybe it was part of Fort Hamer," Sellars said, as a group of visitors from the arts council explored the ruin recently.
Bill Burger, a Manatee County archeologist who checked the ruin Thursday, said that while the building is historic, it was never a fort.
The building is a rectangular shape with three narrow slit windows on the south side and two on the north side. In contrast to the straight lines and 90-degree angles of the rest of the building, the east side walls converge at a 45-degree angle. On the north side of the building is a square-shaped room, whose walls extend only waist high.
Iris McClain, treasurer for the arts council, agrees that the building is not tabby.
"I looked at it with a magnifying glass and could see no sign of crushed shell," McClain said.
But based on her knowledge of cement and plaster -- her father was a mason -- she believes the building predates the 1940s.
"Why would anyone build a structure like that in the 1940s?" she said.
Vivian Buice has lived all of her 86 years in Parrish and said she never knew about the ruin.
"I never came this way," she explains.
But she believes the property was part of -- or close to -- a large parcel called Lundy's Landing that extended to the Manatee River and once had a school, a post office and a grocery store.
"Mama said the river was real deep back then," Buice said.
In researching the archives of the Manatee River Journal from the late 19th century to early 20th century, McClain found that Erie farmers grew tobacco, rice, cabbage, cauliflower and a variety of fruit. The fruit was taken to a wharf along the river and loaded onto steamships to be brought to market.
At the center of the property was an artesian spring that attracted visitors who believed it had youth rejuvenating properties, Buice said. The well was long ago capped.
Cathy Slusser, director of historical resources for the Manatee County Clerks Office, said she has found no records that indicate what the ruin could have been.
As to whether it could have been the Erie Post Office, she said post offices historically were in homes or in stores and could move from one place to the other.
"You just don't know. It depended on who got the contract to operate the post office," Slusser said.
James A. Jones Jr., East Manatee reporter, can be contacted at 941-745-7053 or on Twitter @jajones1.