Auburn Valley State Park in Yorklyn, Delaware, is home to the historic Marshall Mansion and the Auburn Heights Preserve, where visitors can tour the grand estate. The Marshall Steam Museum is another highlight, featuring interactive exhibits and educational programs that delve into the history of steam technology and transportation. The park also has scenic walking trails are perfect for hiking and biking, providing beautiful views and opportunities for bird watching. You can also hike from the park up to Marshall Bridge Preserve, which features hiking trails in the neighboring state of Pennsylvania!