The Greek Revival commercial building at 116 Main Street in Sheffield was built c. 1845. In the early twentieth century it was known as the Cassidy Building and housed Sheffield’s Post Office, with James G. Cassidy as postmaster from 1914 to 1922, succeeded by Miss Beatrice Ellis from 1922 to 1934. The building was again the Post Office from 1957 to 1966, with J. Wesley Warren as postmaster. The building has housed a number of antiques dealers over the years. Most recently, it is home to Samuel Herrup Antiques.