NATCHEZ — Two Natchez antebellum houses were named in the state’s top 12 architectural sites Tuesday.

Longwood, a house left unfinished for nearly 150 years won first place in the Mississippi chapter of the American Institute of Architects’ contest.

Mississippi residents voted online from July 4 through Labor Day.

Longwood won the top spot with 1,809 votes, and Dunleith placed fifth with 1,034. Roughly 20,000 votes were cast for the 32 nominated buildings, AIA Mississippi Executive Director Joe Blake said.

“The fact that many outside of Natchez thought it was the No. 1 spot is so good for our town,” said Cindy Bailey, president of Pilgrimage Garden Club, which owns Longwood. “We’re thrilled.”

The building is the largest octagonal home in the country, Historic Natchez Foundation Director of Education Mimi Miller said.

One reason it won might be its unique architecture, and another might have been its story, she said.

“It’s a building frozen in time,” Miller said. “It was under construction, and the family lived in it until 1960.”

People who visit the house are amazed at the house, Manager Anna James said.

“It’s so completely different form other pre-civil war antebellum structures in the area,” James said.

Because the majority of the building is unfinished and unfurnished, it makes the architecture more accessible, tour guide Harry Boschieri said.

“We get architects, builders and architecture students from all over the country,” Boschieri said.

While the first-place winner is unusual, the fifth-place winner, Dunleith, is iconic, Manager John Holyoak said.

“When people think of a big, grand house, people think of columns and the second-floor balcony,” he said. “That’s the kind of image Dunleith has. It gives the vision of the grand past of the old plantation homes and history.”