23 Beekman Place, Residential penthouse in Turtle Bay, Manhattan, US

23 Beekman Place is a five-story brownstone of about 1869 in Turtle Bay, Manhattan, with a four-story steel penthouse added above it by Paul Rudolph between 1977 and 1982. The penthouse, with light concrete wall panels and exposed steel painted brown, cantilevers slightly over the street; its rear walls hold full-width windows facing the East River. The base keeps a rusticated first story with three round-arched openings and three windows on each of the upper floors.

The land was once part of James Beekman's country estate, and Beekman Place was laid out in the 1860s with four-story brownstones. This house was built around 1869 as a five-story brownstone. In the first half of the 20th century it was occupied by actress Katharine Cornell and her husband, director and producer Guthrie McClintic. Paul Rudolph leased a fourth-story apartment in 1961, bought the whole building in 1976, and from 1977 to 1982 added the steel penthouse; the Landmarks Preservation Commission designated it in 2010.

The building's name comes from Beekman Place, laid out in the 1860s on land once part of James Beekman's country estate; he was a descendant of Dutch colonist Willem Beekman. In the first half of the 20th century the brownstone was home to actress Katharine Cornell and her husband, director and producer Guthrie McClintic. The Landmarks Preservation Commission designated it a landmark in 2010.

The building sits on the eastern sidewalk of Beekman Place between 50th and 51st Streets, with a 20-foot frontage and a depth of 100 feet. The entrance is reached by steps descending from the sidewalk to a slightly depressed first story, where a black-painted metal awning on four columns stands before the arched Adamesque door. The west facade faces Beekman Place; the east side overlooks the FDR Drive and the East River.

The steel penthouse, added between 1977 and 1982, was cantilevered slightly over the street; neighbors objected that it would draw attention to the enclave and block their East River views. The exposed steel sections were painted brown to contrast with the lighter concrete panels.