Radnor Township is a municipality in Delaware County, Pennsylvania, United States. As of the 2000 census, the township population was 30,878. Radnor Township lies along the Main Line, an elite collection of highly affluent Philadelphia suburbs. Radnor Township apartments for rent comparison page shows most up to date rent information on Radnor Township apartments and houses. Rent information is obtained from multiple rental sources but we cannot guarantee their accuracy.