Lewisburg is a borough in Union County, Pennsylvania, United States, 30 miles south by east of Williamsport and 60 miles north of Harrisburg. In the past, it was the commercial center for a fertile grain and general farming region. The population in 1900 was 3,456; and in 1910, 3,081. The population was 5,620 at the 2000 census. It is the county seat of Union County. Located in central Pennsylvania, on the West Branch Susquehanna River, Lewisburg is northwest of Sunbury. It is home to Bucknell University and Lewisburg Federal Penitentiary. Its 19th century downtown was recently placed on the National Register of Historic Places. Lewisburg apartments for rent comparison page shows most up to date rent information on Lewisburg apartments and houses. Rent information is obtained from multiple rental sources but we cannot guarantee their accuracy.