Williamstown is a borough in Dauphin County, Pennsylvania, 38 miles northeast of Harrisburg. Formerly, hard coal mines were here, as well as hosiery mills. In 1900, 2,904 people lived here, and 2,934 lived here in 1910. The population was 1,433 at the 2000 census. Williamstown apartments for rent comparison page shows most up to date rent information on Williamstown apartments and houses. Rent information is obtained from multiple rental sources but we cannot guarantee their accuracy.