Time capsules run a high risk of being forgotten once they're buried. In 1989, the organizers of the Washington State Centennial Time Capsule took measures to guard against such loss.
The Time Capsule has some unusual features. For one, the big green safe is not buried; it's on display on the ground floor of the state Capitol. That makes it possible to update the capsule at regular intervals—in this case, every 25 years.