The estate was created by Howard Gould, the son of financier and railroad tycoon Jay Gould, who purchased the land in 1900 and 1901. Castle Gould was designed by architect Augustus N. Allen in 1902 to look like Ireland’s Kilkenny Castle and was completed in 1904.
Castle Gould was intended to be the main house, but when Mr. Gould’s wife decided she didn’t like it, he proceeded to build Hempstead House as their residence.
This building once contained the stables and carriages and servants’ quarters for the Hempstead House estate. It is now part of the Sands Point Preserve.
Castle Gould and Hempstead House are located on what is now called Sands Point Preserve. Most of the out-buildings, including the limestone stable and servants quarters now called Castle Gould, were completed by 1904. The design of Castle Gould was based on Kilkenny Castle in Ireland.
The main residence, called Hempstead House, designed in the style of a Tudor manor house, was completed in 1912. The building features an exterior of granite and Indiana limestone, the latter stone being used for hte decorative elements. The massive structure is 225 feet long, 135 feet wide, has 3 floors, 40 rooms, and an 80 foor tower. It was considered one of the most opulent homes on Long Island’s Gold Coast.
Howard Gould sold the estate to Daniel Guggenheim in 1917. Daniel gave 90 acres of the estate to his son Harry F. Guggenheim who built his home in the style of a Normandy manor house.
In 1942, Castle Gould, Hempstead House and 162 acres were donated to The Institute of Aeronautical Sciences. The institute leased, then sold the property to the United States Navy. The navy used the property for the design and testing of electronic systems. In 1967 the Navy moved their operations and the property was declared government surplus. In 1971, Nassau County acquired 127 acres for public recreational use. Also in 1971, Harry Guggenheim died and in accordance with his will, most of his 90 acre estate was deeded to Nassau County for use as a museum site.
In 2008 Nassau County empowered The Friends of Sands Point Preserve to take over the running of the preserve.