A dead drop is a location used to secretly pass items between two people, without requiring them to meet.
Spies have been known to use dead drops, using various techniques to hide the items and to signal that the drop has been made.
The dead drop spike is a concealment device which has been used since the late 1960s to hide money, maps, documents, microfilm, and other items. The spike is waterproof and mildew-proof and can be shoved into the ground or placed in a shallow stream to be retrieved at a later time.
See also