The cave was discovered by accident while digging a well 40 feet deep to supply water for a winery.
The crystals are composed of strontium sulfate, which is used in the manufacture of fireworks to produce a red color.
Because the cavern is a geode, the crystals grew inward toward the center of the cavity.
The cave was once mined for its celestite, but the owners realized tourism offered more long-term value.
Many of the original crystals were removed for industrial purposes before the cave was protected.
Crystal Cave is the world's largest known geode, located beneath Heineman's Winery on South Bass Island in Lake Erie. The cave features walls lined with strontium sulfate crystals, known as celestite, which can reach up to 18 inches in length. Discovered in 1897 by Gustav Heineman while digging a well, the cave was originally used as a source for water. The chamber measures approximately 30 feet in diameter. Visitors view the cavern from an elevated walkway that surrounds the interior space. The site serves as a functioning component of the adjacent winery operations. Its discovery led to the preservation of the crystals as a geological tourist attraction.
From the stairway entrance looking down into the center of the geode.
Combine your tour with a wine tasting at the surface winery.
The cave is small, so expect the underground portion of the visit to move quickly.
Check the ferry schedule before heading to the island, as transportation is dependent on Lake Erie weather conditions.
Attempting to visit during the off-season without verifying island accessibility, as the ferry service to Put-In-Bay is extremely limited or suspended in winter.
Open seasonally from spring through autumn; closed during winter months.
No touching the crystal walls; wear comfortable, non-slip footwear as the ground can be uneven.
