1. Shelter Rock is the visible portion of a very large boulder (a "glacial erratic") located about forty yards to the west of Shelter Rock Road and about half a mile south of Northern Boulevard. Though it is not located in the Herricks district, it is the area's most prominent topographic landmark and has been honored in the names of numerous public and private institutions. It is apparently the largest exposed boulder on Long Island, though a few others are close in size, and is believed by many scientists to have been deposited at its location by a glacier some 11,000 years ago
2. No one knows for sure why it is called Shelter Rock or who started calling it that. This is the name that stuck by the late 19th century, but at times it was also referred to as Split Rock and Milestone Rock. There are several similar stories about the name, none of which are documented: The overhang on the rock's south side was used as shelter by Europeans in colonial times; it was used as shelter or as a council meeting place by Indians in ancient times; in 1956, official Nassau County Historian Jesse Merritt wrote that, after consultation and consideration, the rock must have gotten its name by serving "as a natural shelter for livestock"
3. Before the rock became part of the vast Whitney Estate ("Greentree") in 1903, it was part of the farm of William Chester, who told a newspaper correspondent in 1896 that his sheep certainly used the boulder for shelter ("It is from this fact that the rock got its name" stated the New Haven Register) . In 1946, an American Museum of Natural History survey team found Indian arrowheads and other artifacts near the boulder, estimated to date back to 1000-1100 A.D. This gave the "Indian shelter" story of the name a big boost, though no Indian source speaks to the issue
4. The measured size of the rock is 54 x 40 x 16 feet, and its weight is estimated to be approximately 2,600 tons
5. In colonial times, Shelter Rock was not considered particularly special. There were a number of other very large boulders dotting the north shore. The others were broken up, mostly to make the stone fences that divided farms. There was originally another very large boulder not far from Shelter Rock. In the 1890s, when a few local highways were first being macadamized (hard surfaced), Mr. Chester was offered a large sum of money for the rock. Engineers thought is could be broken up for high quality surfacing material. Mr. Chester refused the offer
6. Interest in Shelter Rock has ebbed and flowed over the decades. In the late 1950s, there was a resurgence of local interest in the boulder, spurred by a state plan to demolish the landmark as part of the widening and straightening of the nearby road. State engineers announced in July 1958 that they would use a system of retaining walls to support the roadway and that the rock would be preserved. For many years, locals had usually referred to that road as Shelter Rock Road, but it was only after that reconstruction that its official name, Old Courthouse Road, was dropped completely. Soon, the name Shelter Rock was featured conspicuously in numerous local endeavors, including: Shelter Rock Jewish Center (September 1958), Shelter Rock Tennis Club (1959), Shelter Rock Public Library (organized 1960-1961), Shelter Rock Junior High School (opened 1966), Shelter Rock Elementary School (Manhasset Public Schools, opened 1968)
7. Shelter Rock and the land around it are now owned by the Greentree Foundation, a not-for-profit organization which uses the property to host international meetings in pursuit of peace and other philanthropic endeavors