Field Notes Ohio

Ohio's parks, forests and wildlife areas with camping, the ancient mounds beside them, and the Buckeye Trail that links them. Stories, trails, wildlife, and where to eat and fuel up nearby. Book campsites on ReserveOhio.
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The Buckeye TrailA 1,444-mile blue-blazed loop around Ohio, with all 26 sections.
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Mounds & Earthworks43 ancient sites, including the Great Serpent Mound and the Newark Earthworks.
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Historic Sites39 places, from Fort Steuben and Zoar to Camp Chase and the Rankin House, from the frontier to the Civil War.
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Road Trips33 drives, from the Lincoln Highway to the Morgan Heritage Trail.
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Lake Erie Beaches20 public beaches from Conneaut to Toledo and the islands, with a map.
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Oddities & Roadside Attractions19 giants, ghosts and folk-art stops, plus a Mothman just over the line.
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Caves & Caverns12 show caverns, recess caves and rock shelters, with a map.
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Waterfalls34 falls from the Cuyahoga Valley to the Hocking Hills, with trail notes and a map.
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Explore Ohio

One map for every park, mound, historic site, beach, cave, waterfall and oddity in the app.

Lake ErieWest Virginia27 places277 places77 places73 places35 places519 places1913 places1319 places1916 places168 places810 places1010 places109 places98 places820 places204 places43 places3Barkcamp State Park4 places47 places77 places76 places69 places917 places173 places3Harrison Lake State Park2 places2Forked Run State Park3 places32 places26 places610 places103 places32 places2

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117 parks in 7 regions

Crystal Cave at Heineman's Winery

Put-in-Bay · Ottawa County
Geode cave

Visiting information you can trust

Check before driving — this site is seasonal, approximate, privately run, or otherwise uncertain. Confirm hours and access with the official source above.
Content last reviewed
September 2026 — this is when Field Notes Ohio's content was last checked, not a live status.
Primary official source
Official page
Location confidence
Approximate — boundary or exact point not confirmed
Approximate location, use the address
Seasonal access
Public season April 21 to October 26; check the operator for tour times.
Check current conditions
Official conditions or closures
Reservations or tickets
Tickets or admission info

Prices, hours, closures, campsite availability and trail conditions shown elsewhere on this page are not live — always confirm with the official source before you go.

A cave lined with blue-white celestite crystals, billed as the world's largest geode, discovered while digging a well in 1897.

Type
A geode cave, not a limestone cavern; its walls are covered in celestite (strontium sulfate) crystals
Crystals
Celestite crystals 8 to 18 inches long, some up to about 3 feet wide
Discovered
1897, by workers digging a well for the winery 40 feet above; opened to the public in 1900
Tour style
A guided tour, offered as a combo with the winery's wine cellar
Season
Public season April 21 to October 26, per the operator
Access
Reached by ferry or boat to South Bass Island; confirm any step or mobility details with the operator

The story

In 1897 workers digging a well for Heineman's Winery on South Bass Island broke into a cave covered in whitish-blue crystals. Gustav Heineman, who had founded the winery in 1888, named it Crystal Cave, excavated it and opened it to the public in 1900. The original cave was much smaller than it is now: crystals were harvested and sold to make fireworks, and the cave has since been enlarged.

The cave helped the winery survive Prohibition. When the Volstead Act took effect in 1919, most of the island's 17 wineries and vineyards failed, but Heineman's, under Gustav's son Norman, stayed in business by selling unfermented grape juice, running a taxi service and giving tours of the cave.

The world's largest geode is the operator's claim. The map pin is approximate.

Stay on the marked trails and official tours. Caves are fragile and can be dangerous, and entering any cave or crevice that is closed, unmarked or not open to the public is unsafe and unauthorized.

Visiting

Status
Open seasonally
Season and hours
Public season April 21 to October 26; check the operator for tour times.
Cost
See the operator.
Phone
419-285-2811
Please note
Confirm details with the winery; a ferry or boat is needed to reach the island.
Address
978 Catawba Ave, Put-in-Bay, OH 43456
More information →DirectionsShow on the map

The pin on the map is approximate; use the address or the operator's directions.

Seasons, tours and access can change. Confirm with the operator or park before a long drive; where a closure alert applies, check current conditions.

Parks nearby

South Bass Island State Park
About 1 miles · South Bass Island State Park, with camping and a small beach.
Open
Middle Bass Island State Park
About 4 miles · A quiet island park.
Open

Road trips

Lake Erie Coastal Ohio Trail
A road trip that passes near this stop
Open

Related

Perry's Victory and International Peace Memorial
A 352-foot column for the Battle of Lake Erie
Open

Details last checked 2026-09-22. Confirm hours and prices before you go.