The Road… traverses Time—Time past, Time to come, Time that could have been, and Time that might yet be. Some people have the ability to access the Road and travel it from Time to Time and world to world.
With regard to the plot "Sleeping Mines of Elathon":
You manage to get the water wheel in the mine working which operates a pump to clear the flooded lower levels. As you explore the dank tunnels of the lower galleries, you can hear the creaking of the wheel above. You enter a low-ceilinged passage and are crawling on your backs, when the creaking stops. The water starts seeping wetly around the back of your head...