Hempstead House

Howard Gould, a son of the financier Jay Gould, bought undeveloped land at Sands Point in 1900 and 1901. His first building was Castle Gould, designed in 1902 by Augustus N. Allen and completed in 1904. Modeled on Kilkenny Castle in Ireland, it is a limestone building of about 100,000 square feet. Gould's wife, the actress Katherine Clemmons, did not want it as her home, so it was used as the stable, carriage house and servants' quarters, and Gould began a second house across the property.

That house, which Gould called Castlegould, was designed by the firm Hunt & Hunt and completed in 1912. It is a Tudor Revival manor of about 50,000 square feet on three stories, 225 feet long and 135 feet wide, faced in granite and Indiana limestone. Its 40 rooms include an entry foyer 60 feet tall, a walnut-paneled library modeled on a palace of King James I, and a billiard room fitted with carved oak from a 17th-century Spanish palace. The Goulds separated while the house was under construction, and their marriage ended in a public divorce.

In 1917 Gould sold the estate to the mining magnate Daniel Guggenheim and his wife, Florence, who renamed the house Hempstead House for its views over Hempstead Harbor. They used it as a summer residence, with a large household staff and more than 200 farm and grounds workers. In 1923 Daniel gave 90 acres to his son Harry F. Guggenheim, who built Falaise on the bluffs above Long Island Sound. Daniel Guggenheim died at Hempstead House on September 28, 1930. Florence then closed the house and built a smaller residence, Mille Fleurs. In 1940 she sold the furnishings at auction and opened the house to 75 refugee children from Europe.

In 1942 Florence Guggenheim gave 162 acres, including Hempstead House and Castle Gould, to the Institute of Aeronautical Sciences. The Institute leased and then sold the property to the U.S. Navy in 1946. The Navy's Special Devices Center, later the Naval Training Device Center, worked there until it moved to Orlando, Florida, in 1967, when the site was declared surplus. Nassau County then took the land for public recreation. The Conservancy dates the county's acquisition of 127 acres to 1971, while a 2016 Long Island Press history says the county received 128 acres in November 1967. Harry Guggenheim died in 1971 and left Falaise and its 90 acres to the county as a museum site.

The estate was listed on the National Register of Historic Places in 2006 as the Gould-Guggenheim Estate. Today the 216-acre Sands Point Preserve is owned by Nassau County and managed by the nonprofit Sands Point Preserve Conservancy. Hempstead House holds concerts, lectures and private events and is often used for film and television work. Castle Gould houses the visitor center and a sound stage and is not open for tours. The preserve's trails, garden and beach are open Wednesday through Sunday for an admission fee, and visitors can see the interior of Hempstead House only on scheduled guided tours.