thornwood
Thornwood once had a large and thriving Westchester marble quarry near its heart, the intersection of Route 141 and Kensico Road (known as Four Corners). Dating back to 1845, the quarry supplied white marble which helped build St. Patrick's Cathedral (hence the name of Marble Avenue which runs through the hamlet). The quarry pit was filled in during the mid-1980s, and the Town Center shopping mall was constructed over it.
It is the home to the North American headquarters for the Carl Zeiss Corporation, a multinational German manufacturer of optical systems, industrial measurements and medical devices.
Thornwood is part of the Mt. Pleasant Central School District, which includes the Hawthorne Elementary, Columbus Elementary School, Westlake Middle School and Westlake High School. The former Thornwood Elementary School was closed and converted to condominiums in the 1980s, and the former Thornwood Junior High School later became Columbus Elementary School.