Mumlava is a mountain stream in the Czech Karkonosze Mountains. Near Harrachov (about 1.5 kilometers east of the village center) is the Mumlava Waterfall (Czech: Mumlavský vodopád). The cascade is about 10 meters high and very wide. The water of the mountain stream falls from granite blocks, forming deep evaporative cauldrons at the bottom called Čertova oka (Devil’s Eye). The waterfall can be admired either from an observation deck or from a small bridge over the Mumlava River.