Auburn Heights Preserve is a state park, located in Yorklyn, Delaware, United States. The park, which is around 360 acres, preserves the former home and estate of the Marshall family as well as portions of the family's former mills alongside the Red Clay Creek and additional land purchased by the state. The preserve contains several miles of trails open to walking, biking, and antique cars, and the state owns conservation easements on 160 acres of privately owned land adjacent to the park to help maintain the park's rural character.The park also features what the state bills as the largest collection of operational steam cars in the world, and a miniature coal-powered train that runs on tracks encircling the estate. The mansion, mills, and steam museum were added to the National Register of Historic Places in 1980 as the Auburn Mills Historic District.Park historyInterest in preserving land near the Red Clay Creek was first expressed to the state by local residents and conservation groups in 2000. With the nearby National Vulcanized Fiber company looking to downsize, there was a general agreement among advocates that an opportunity for conservation had presented itself. Tom Marshall, the owner of a local estate, began donating portions of his land to the Delaware Nature Society for conservation purposes. The state began acquiring land for a preserve in 2002, with a purchase of 104 acres of NVF land for $3 million and a purchase of 65 acres of Marshall's old land from the Delaware Nature Society for $2.3 million.
