Elysburg is a census-designated place (CDP) in Ralpho Township, Northumberland County, Pennsylvania, United States.

[3] The area's biggest attraction is Knoebels Amusement Resort, which is known for having three wooden roller coasters and free admission.

Elysburg's terrain is mostly gently rolling, with some steep hills in the northeastern part of the CDP.

[4] As of the census[7] of 2000 there were 3,937 people, 1,746 households, and 1,188 families living in the CDP.

28.0% of all households were made up of individuals, and 15.6% had someone living alone who was 65 years of age or older.