The park is located just to the south of Petersburg off of I-85. It's where Grant's troops punched through General Lee's lines, forcing the evacuation of Petersburg after a nine month siege. Lee surrendered one week later.
The park strives to be the preeminent Civil War experience, and I think they have succeeded. The new Musuem of the Civil War Solider is exceptionally well presented with both video and audio components.
There are also very well preserved earth works, a plantation house and living history activities.