In honor of the 16th anniversary of National Fossil Day, Valley Forge National Historical Park is celebrating the amazing Ice Age fossils of Valley Forge with a day of interactive, family-friendly activites and special programs. Learn about mastodons, saber-toothed cats, giant ground sloths, and lots of other incredible critters that walked the ancient landscape of Valley Forge hundreds of thousands of years before George Washington and the Continental Army ever set foot here. When: Saturday, January 17, 2026 between 10am and 4pm Where: Visitor Center at Valley Forge Note: Valley Forge Fossil Day was originally scheduled for Saturday, October 11, 2025 but was unable to take place due to the lapse in appropriations of the federal government. The event has been rescheduled for Saturday, January 17, 2026.