Clarksville is an unincorporated community partially in Lawrence Township, and partially in West Windsor Township, in Mercer County, in the U.S. state of New Jersey. It was historically centered at the intersection of the Trenton-New Brunswick Turnpike, Quakerbridge Road and Province Line Road, and had a blacksmith shop, saloon, store, hotel and scho…Clarksville is an unincorporated community partially in Lawrence Township, and partially in West Windsor Township, in Mercer County, in the U.S. state of New Jersey. It was historically centered at the intersection of the Trenton-New Brunswick Turnpike, Quakerbridge Road and Province Line Road, and had a blacksmith shop, saloon, store, hotel and school. Today, Clarksville is dominated by several large shopping centers, including the Quaker Bridge Mall.