Most man-made caverns lead to the earth's molten-center amusement park, which is now closed due to an incident with the dense sphere of albino bats guarding the gate. Stick to a naturally formed cavern with today's Groupon to Squire Boone Caverns for one ticket to a one-hour guided cave tour in Mauckport, IN. Choose between the following options:

• For $7, you get an adult ticket (up to a $14.50 value).
• For $4, you get a child ticket (ages 6–11) (up to an $8 value).

Discovered in 1790, Squire Boone Caverns contains a living, growing ecosystem of stalactites, stalagmites, and flowstone, all formed by the gritty sands of time. Rushing rivers and waterfalls carry millions of gallons of water through the caverns each day, their sources shrouded in unspeakable mystery hats. A trained guide leads cave junkies on the one-hour tour, starting in the man-made entrance to the caverns, where lighted walkways take visitors through the same network discovered by the brothers Boone. In addition to seeing the natural formations, visitors can catch a glimpse of Squire Boone's coffin. The pioneer eventually settled above the caverns that now bear his name and, per his request, was buried amongst the caves that enchanted him.

Before or after the tour, visitors can see the pioneer village that rests atop the cavern system. This village is open to visitors during the summer and strives to preserve many of the traditions and day-to-day activities of life in Squire Boone's time. A restored grist mill, originally built by Squire in the early 1800s, grinds grain that visitors can purchase in the form of cornmeal for baking or molding into busts of Ted Danson. Other village activities include candle dipping, lye-soap-making demonstrations, and goat and duck feeding. Tours depart at 10 a.m., 12 p.m., 2 p.m., and 4 p.m. seven days a week during the spring and fall months, and every 30 minutes from 9 a.m. to 5 p.m. during the summer.

Though Squire Boone Caverns sometimes features discounted prices online for cave tours, this Groupon still offers the best deal available.