The Underground River Adventure begins in the Hot Springs, where you will design stepping stones over the pool. The map of the island, divided into quadrants, will help you navigate.

In Quadrant II, you will find rows of arched doors that will lead you to new problems. Beyond this cavern lies a new tunnel -- be careful where you step. Check your backpack, buy hints, and look closely at Descartes' Secret File.

When you reach the Underground River, the frogs and fish will help you find your way. Hold on tight to the raft when you're ready to go on! The raft may be a little unstable....