The Passport To Your National Parks® program was developed in 1986 as a guide to America's national parks. A fun feature of the Passport® program is collecting cancellations from each park visited. The cancellations are stamped in the Passport® book. These ink markings record the name of the park and the date of the visit, which is a great way to commemorate your time in each park. This pin features the Passport® book and a stamp for Delaware Water Gap National Recreation Area, PA-NJ.