252 East 57th Street

Another project that appears to be moving forward is 252 East 57th Street, a condo-rental tower at Second Avenue in Midtown East. Demolition and digging began at the blocklong site last summer, but few details have been shared about what might end up there.

The principals of the World-Wide Group, which is developing the project with Rose Associates, would not agree to an interview or provide renderings. It is unclear whether the original angular Skidmore, Owings & Merrill design survives; it was unveiled to much acclaim when the project was announced about eight years ago.

Beth McBride, a spokeswoman for the project, said the building would be 700 feet tall and that sales would begin later this year. In its current configuration, she said, the 65-story tower will contain about 93 condos atop 173 rentals, plus 33,000 square feet of storefront along Second Avenue and East 57th.

And Andrew Singer, the chairman of Singer & Bassuk Organization, a commercial brokerage, who until recently had served as an adviser to the project for years, added other specifics. He said this winter he helped line up a $450 million loan for the project from Starwood Property Trust for what will be a $600 million project.

Mr. Singer, who recently brought Rose into the project, said it’s been great to see progress. “To say the least, it’s taken a long time,” he said. “They didn’t build the pyramids overnight, either.”

The mixed-use project, a public-private partnership, is complicated. The apartment site and a next-door parcel, which are owned by the city, once included two schools. First, World-Wide had to build an off-site temporary home for one, Public School 59, in a converted hospital building on East 63rd Street. World-Wide later sold that structure to the city, and a new public school moved there.

At the same time, the developer tore down the old school building on East 57th Street and constructed a taller home for P.S. 59 and the High School of Art and Design, which had been next door. A Whole Foods supermarket was installed at the base. Then the High School of Art and Design’s old home was torn down, paving the way for the construction site visible today.