Knapsack

A knapsack is a bag that can be carried by strapping it to one's shoulders.

While taking a rest break from a bike ride next to a tree and a boulder in Cave County, Marvin White and Wendy Harris have their knapsacks with them, and they believe that someone moved them, but what they don't realize is that the tree and the boulder got up and moved themselves.

External Link

 * Knapsack at Wikipedia