A religious shrine in West Bend, Iowa - the Grotto is said to be the largest in the world. It is also considered to be the worlds most complete man-made collection of minerals, fossils, shells and other petrifications. The shrine includes a museum and is a highly visited tourist attraction.
The Shrine of the Grotto of the Redemption is a religious shrine located in West Bend, Iowa, in the Roman Catholic Diocese of Sioux City. A conglomeration of nine grottos depicting scenes in the life of Jesus, the Grotto contains a large collection of minerals and petrifications and is believed to be the largest grotto in the world.
It is also "considered to be the world's most complete man-made collection of minerals, fossils, shells, and petrifications in one place." The total value of all the rocks and minerals which make up the Grotto is over $4,308,000. Over 100,000 people visit the Grotto each year.
The shrine includes a museum with precious and semiprecious stones from throughout the world, and photos and artifacts about the construction of the shrine.Provided By: https://en.wikipedia.org/wiki/Grotto_of_the_Redemption