Crucial to our existence, water sustains all life on Earth. Following the old adage, “What goes around comes around,” water moves continuously through the stages of the hydrologic cycle (evaporation, condensation, and precipitation). How does our drinking water fit into this hydrologic cycle? Where did the water we drink fall as precipitation? Did this water percolate down into the ground as part of a groundwater system, or did it remain on the surface as part of a surface water system? What path did this water follow in order to become our drinking water? This lesson will explore the hydrologic cycle and water’s journey to our glass.