Fountain of Youth
Allison Park, Pennsylvania
In 1938, a natural spring in rural North Park was sheltered within a rock grotto built by the WPA. The intent was to make it look classically Roman, but today it looks more like something out of The Lord of the Rings. The spring was capped with a pump handle set into a hillside, and over it was a stone disk inscribed, "Fountain of Youth."
Locals enjoyed this youth-giving water until May 11, 1955 -- when the pump handle was abruptly removed and the Spring was declared contaminated by "coliform organisms" (i.e. bodily fecal waste). No explanation was given for the source of this sudden corruption (the Spring's water had been declared pure only two years previously) and the fountain part of the Fountain of Youth has remained inaccessible to the public ever since.
The rock work around the Spring entrance was repaired in 2005, and the Fountain of Youth disk was remounted in 2009. Still no pump handle, though.