Philadelphia is a city in Loudon County, Tennessee, United States. Its population was 533 at the 2000 census. It is included in the Knoxville, Tennessee Metropolitan Statistical Area.
Philadelphia is located at 35°40′42″N 84°24′5″W / 35.67833°N 84.40139°W / 35.67833; -84.40139 (35.678236, -84.401430). The town is situated along Sweetwater Creek, which empties into the Watts Bar Lake impoundment of the Tennessee River a few miles to the north.
Philadelphia is centered just northwest of the junction of U.S. Route 11, which connects Philadelphia with Loudon to the north and Sweetwater to the south, and State Route 323 (Pond Creek Road), which connects Philadelphia with Interstate 75 to the west.