Wright designed six hotels, including the Park Inn Hotel in Mason City, Iowa. (Wright on the Park)

Work is under way at the last remaining hotel Frank Lloyd Wright designed, the Park Inn Hotel in Mason City, Iowa, which has been closed since 1972.

Wright designed the Park Inn Hotel and adjacent City National Bank in 1910.

In September, Wright on the Park, Inc., the organization that is overseeing the work, bought the City National Bank, coming a step closer to fulfilling its mission to "own, restore, preserve, and maintain" the hotel and bank building.

"It stands at a pivotal point of [Wright's] career," Robert McCoy, a member of Wright on the Park, told Preservation Online. "There are not many buildings of this stature left."

The group plans to refit the bank building, which was remodeled in 1926, to make room for an elevator. Its top floor will provide an extra six rooms for the hotel, according to Ann MacGregor, executive director of Wright on the Park, Inc.

So far, workers have restored the lobby's terra cotta tiles and 25 panels of art-glass skylight in the hotel.

The hotel's restoration has stalled in the past. In 2005, the city reclaimed the building from a foundation after work was not completed in the allotted five years.

The nonprofit, which formed in 2005, convinced the hotel's owner, the city of Mason City, to transfer the building to the group in 2006.

Seven years ago, the project won a matching grant of $500,000 from Save America's Treasures, a public-private partnership between the National Park Service and the National Trust for Historic Preservation.

Wright on the Park hopes to complete the restoration by the hotel's centennial in 2010.

Read more about the Park City Inn on Preservation Online>>

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