Cave bacon, looking like crispy fried bacon strips but actually made of calcite striped with bands of iron oxide, dangles from the ceiling. Some portions of the cave are a tight squeeze for two passing boats, but none so much as the Strait of Gibraltar. Here, two giant rocks close the gap across the river and the cavern walls squeeze tight. Guests must duck to avoid scraping their heads as they enter the largest chamber in the cave, the Dry Room. The Dry Room huddles under a jumble of huge blocks of limestone that crashed from the cavern ceiling.
Stalactites decorate the ceiling.
Further along the river, lights play across the shimmering surface of the Frozen Niagara, a tall flowstone formation. Nearby, the delicate stalactites and stalagmites of the Garden of the Gods provide a landscape in miniature. As guests oooh and aah over a succession of blue, green, red and yellow lights washing over formations to create an underground sunset in the Colored Lights room, ducks paddle up to the boat, looking for a handout. Sunlight streams in around the next bend in the river. A narrow passage was widened so the boats could reach Lake Nittanee, the farthest point on the tour.