Passport in Time
„The goal of PIT is to preserve the nation’s past with the help of the public. As a PIT volunteer, you contribute to vital environmental and historical research on public lands. Your participation helps us not only to protect and conserve the sites, memories, and objects that chronicle our collective past, but also to understand the human story in North America and ensure that story is told to our children and grandchildren. We cannot do it without you!“
(http://www.passportintime.com/)
