7. **The Vanishing Rivers Mystery**

One of the most fascinating stories of Yellowstone centres on rivers that seem arise and vanish without reason. Early adventurers claimed to have discovered rivers that would vanish under ground and then unexpectedly surface miles away. Until geological research showed the intricate network of subsurface channels and thermal factors that truly do cause some streams to vanish and resurface elsewhere in the park, these stories were sometimes written off as tall tales. Stories of adventurers chasing these disappearing rivers and finding secret caverns and underground rooms bursting with crystal formations and enigmatic steam vents abound in the mythology. According some accounts of the story, Native Americans used these subterranean rivers as covert paths of movement during times of war.