A Hyde Park architectural gem that marked an important transitional period in Frank Lloyd Wright’s architectural career is on the market for $2.5 million.

The Heller House, located at 5132 South Woodlawn Avenue, was designed by Wright and built in 1897, 12 years before he designed the Robie House on East 58th Street and South Woodlawn Avenue. Designated a National Historical Landmark in 2004, the 6100-square-foot home offers significant insights into Wright’s creative and professional development.

“Inside, it’s like the beginnings of Robie House,” said Jack Spicer, chair of the Hyde Park Historical Society’s preservation committee, explaining that the building’s open rooms and use of natural materials bridge Wright’s early architecture with his signature Prairie style.

“Outside, he was still trying to decide what style he wanted to use,” Spicer said. “He was still working toward what looks modern. There are some aspects of Victorian architecture and other aspects of the more open Prairie style.”

Sam Guard, a Hyde Park resident who studies historic Chicago architecture and gives building tours around the area, said that the house’s exterior demonstrates Wright’s attempts to emulate the classical style of most late 19th century homes.

“Wright was a country kid from Wisconsin,” Guard said. “He never had a classical education, much less studied classical architecture. He was an extremely competitive guy. If someone did something, he always wanted to do it better.”

The house’s interior bears many Prairie School characteristics, according to Guard. The hardwood floors and wood door frames are an integral component of the “arts and craft movement,” during which architects wanted to display materials in their natural form.

The Heller House also reflects Wright’s space-saving techniques, and has relatively large rooms for a house in a narrow city lot. Spicer says Wright worked around the spacial limitations by placing the front door on the south end, facing East 52nd Street, rather than in the front on South Woodlawn Avenue.

Commissioned by Chicago meat-packer Isidore Heller, the house was the first of Wright’s Hyde Park homes after he angrily parted ways with his mentor, Louis Sullivan.

The current owners, Emily Novick and Steven Goldstein, have lived there since 2004, but they decided to sell it after Goldstein, physician-in-chief at UCMC’s Comer Children’s Hospital, was appointed provost of Brandeis University last June, according to an interview Novick gave with Chicago magazine last month. The house has been on the market since January 25.

Novick lamented having to sell the house, she told Chicago.

“If you had a Van Gogh painting, would you sell it because it was inconvenient to move it? That’s what this feels like,” she said.