Temple Beth El of Northern Westchester is a Jewish congregation in Chappaqua, New York notable primarily for the fact that the building was designed by Louis Kahn. Although Kahn designed other synagogues, this is the only one of his designs that was built.
According to the National Trust for Historic Preservation, Kahn accepted the commission in 1966, and completed plans for the octagonal sanctuary 6 years later.
References
Temple Beth El of Northern Westchester Wikipedia(Text) CC BY-SA