NEW CANAAN — It was the party of the year, as far as The Glass House was concerned.

People from New York City and local towns gathered Saturday for the annual Summer Party at The Glass House, a 49-acre property with 14 structures, including a glass house, built by architect Philip Johnson between 1949 and 1995. The building was made a National Historic Site following Johnson’s death in 2005.

The June 9 fundraiser was the site’s largest event of the year. Proceeds will go toward preservation efforts on the property, including a brick house restoration project set to begin next year, The Glass House Deputy Director Scott Dreving said.

The 400 attendees of the sold-out event enjoyed a picnic lunch, performances by the musical quartet Brooklyn Rider, and an unexpectedly sunny day.

Prominent contemporary artists Jeff Koons, Lyn Davis and Alex Katz contributed pieces for the silent auction. Rob Wyne’s piece, “The Glass House,” which spelled out “The Glass House” in glass, sold for $20,000.

“It’s a much different experience at the Summer Party than if you come for a tour because you can really explore the grounds,” Todd Challe, a New Canaan resident who lives up the street from the Glass House, said.

“We come every year and love it. It’s nice to have an inside view,” Challe’s wife, Peggy Challe, said.

svaughan@hearstmediact.com; 203-842-2638; @SophieCVaughan1