Bluegrass Underground - 333 feet down and 8 years old this month. They say necessity is the mother of invention, but in our case, it was procrastination. Back in the summer of 2008, Bluegrass Underground was born after our founder Todd Mayo waited too long to rent a pontoon boat for his family's Memorial Day weekend on the Cumberland Plateau. By the time he got there, all the boats were gone, so Plan B was a tour of Cumberland Caverns. When they arrived in the Volcano Room, the lightbulb over Todd's head switched on, surprising his 1-year-old son, Jackson, who was riding his dad's shoulders. "Do you ever have concerts here?" Todd asked the guide. They didn't, but within three months Todd had started Bluegrass Underground.