Cock-Cornelius House

Cock-Cornelius House, also known as Wyckoff-Underhill House, is a historic home located at Locust Valley in Nassau County, New York. It is a 1- to $2 1/2$-story, U-shaped wood-frame dwelling sheathed in wood shingles. The main block is $2 1/2$ stories and five bays wide. The oldest section of the house is dated to the Federal period, about 1790. The house was expanded in the 1840s and in the 1920s-1930s.

It was listed on the National Register of Historic Places in 2006.