This locally owned winery (established in 1888 and still owned by the Heineman family) has the additional attraction of being located above an amazing cave of crystals -- the world's largest geode. The fascinating cave, discovered by winery workers digging a well in 1887, helped the winery survive Prohibition in the early 1900s. Admission to the cave and winery tour costs $6 for adults and $3 for children. Note: They only accept cash. The tour includes a token for a drink at the end of the visit -- wine or grape juice in the gift shop and wine store. Heineman's capitalizes on the Lake Erie islands' ideal grape-growing conditions and produces a variety of award-winning wines, including some ice wine varieties. The Crystal Cave tour requires navigating some steep and narrow stairs. Two small "rooms" in the geode are linked by a narrow tunnel. Claustrophobic folks may be uncomfortable with the quarters, but for visitors not bothered by stairs or small spaces, the cave offers a fascinating glimpse at a beautiful natural phenomenon.