The Municipal Art Society gala celebrates New York, and last night it chose the perfect spot to do so. The event was held at the new One Beacon Court, which was built by New Yorkers with a grand vision.

“It’s fantastically appropriate to have our gala here. The Municipal Art Society is for people who believe in a more beautiful New York, whether it’s a constructing a great new building or saving a community garden,” the society’s chairman, Philip Howard, said.

The building, which is nearing completion, is on the former site of Alexander’s Department Store. The lot was dormant for years before Vornado Realty Trust’s Steven Roth developed the office and residential tower designed by Cesar Pelli, with interiors by Jacques Grange. The bet on the property has paid off for both Vornado and Alexander’s, which is now in the real estate business.

Mr. Roth was at the gala – the very first event held at One Beacon Court. So was Mayor Bloomberg, whose firm, Bloomberg LP, will occupy the offices.

Attendants were on hand to show guests the residential condominiums, soon to be enjoyed by such high-profile tenants as Beyonce Knowles and Brian Williams. Though still very much under construction, the spectacular views, from three exposures, were evident. A selling agent said some of the apartments will be ready in late November or early December.

Robert A.M. Stern, a board member of the society, praised the building. “I love the lights on top; I think it’s fresh looking. The site presented a difficult problem and it’s well solved,” he said. He added: “Most of the society’s parties are in old bank buildings or clubs, which is great, but it’s nice to celebrate something new.”

After some 500 guests enjoyed cocktails in the building’s outdoor circular courtyard, they convened for dinner (by Glorious Food) and the awarding of the Jacqueline Kennedy Onassis Medal to one of the city’s great art patrons, Agnes Gund.

Mrs. Gund noted some common ties with Onassis in her speech: they both went to Miss Porter’s School and sent a child to Concord Academy. But mostly she spoke of her love of New York, “where you can run away without every leaving home.” To further convey her affection, she quoted Dorothy Parker and Cole Porter.

Yet even Mrs. Gund leaves New York once in a while – she’ll head to Ohio later in the month to campaign for Senator Kerry (last night she taped the vice presidential debates). And she’ll be in Sharon, Conn., for Christmas at the home of her daughter Anna Traggio.

Asked if she shared her mother’s passion for her art, Mrs. Traggio said, “I appreciate art, but I’m the jock in the family.” She coaches lacrosse at Hotchkiss and is due with her third child in December.