Pond Pit
In late autumn of 1958, a large pond near Lahaska, Bucks County, Pennsylvania, began to rapidly recede. Within several hours the water completely drained into a 3-foot diameter hole, which had formed in the bottom of the pond. Gradually as the soft mud surrounding the hole collapsed inward, the opening enlarged until it was more than 10 feet across.
Ladders were used to span this pit, enabling observers to view a tunnel leading downward at a sharp angle. Shortly after this dramatic occurrence, a peninsula was constructed over the opening and the pond refilled, leaving no trace of the cave.
In autumn 1958, curious spectators used ladders to bridge the sinkhole and view the mouth of the cave that swallowed the pond.