High and Locust Streets Historic District is a national historic district located in Lockport in Niagara County, New York. The district includes 120 contributing buildings in a predominantly residential area of the city. The district developed between about 1840 and 1936, and includes buildings in a variety of architectural styles, including Greek Revival, Italianate, Queen Anne, Colonial Revival, Classical Revival, and Bungalow / American Craftsman. Located in the district are the separately listed Chase-Crowley-Keep House, Chase-Hubbard-Williams House, and Thomas Oliver House. Other notable buildings include the F.N. Nelson House, Calvin Haines/Alonzo J. Mansfield House, J. Dunville House, Ambrose S. Beverly House, Dr. Martin S. Kittinger House, and F. N. Nelson House/Lockport Home for the Friendless.