Shell Grotto at Margate (UK)
In 1835 Mr James Newlove lowered his young son Joshua into a hole in the ground that had appeared during the digging of a duck pond. Joshua emerged describing tunnels covered with shells.
He had discovered the Shell Grotto; 70ft of winding underground passages leading to an oblong chamber, its walls decorated with strange symbols mosaiced in millions of shells. Is it an ancient pagan temple? A meeting place for some secret cult? Nobody can explain who built this amazing place, or why, or when, but since its discovery visitors from all over the world have been intrigued by the beautiful mosaic and the unsolved mystery.