Every summer, Oregon`s Lost Lake disappears into volcanic tunnels, re-emerg-ing in the f all as streams fill the meadow below.

Located in the Willamette National Forest, the lake reaches its fullest in mid-winter, but dries up by summer when its water drains through two ancient volcanic holes.

These holes, formed 12,000 years ago, allow water to seep into a large aquifer. Lost Lake attracts many summer visitors, but park authorities struggle to prevent people from trying to plug the holes with debris, which could lead to flooding and disrupt the surrounding ecosystem.