Hidden underground in the Germany Valley, the Seneca Caverns are limestone caves full of spectacular stalactites, stalagmites, and flowstone formations. The caves were discovered by humans as far back as the 1400s, when they were used for ceremonies by the Seneca Indians, and they've been open for commercial tours since 1930s. The standard guided tours lead visitors through the cave on a well-lit mile-long path, but if you have an adventurous spirit, you can take the Stratosphere Cavern tour instead, which goes through an unlit portion of the cave. After your tour, you can mine for gems, browse the gift shop, or enjoy a picnic.