The Mumlava Waterfall is one of the most powerful and most visited waterfalls in the Czech Republic — a wide, thundering cascade tucked into the spruce and beech forests of the Giant Mountains, just 2 km from the centre of Harrachov. Its name comes from the German word murmeln, meaning 'to murmur', though in full flow this waterfall is anything but quiet.

Sitting at 760 m above sea level, the waterfall drops nearly 10 metres across a face up to 10 metres wide over granite boulders. It is at its most spectacular in spring, when snowmelt swells the Mumlava River into a roaring wall of white water. In winter, the flow sometimes partially freezes into a dramatic ice fall. During summer's lower water levels, the river splits into several channels, revealing the waterfall's most curious feature — giant potholes known locally as 'devil's eyes', carved by erosion into the granite riverbed. The largest of these hollows reaches 6 m in diameter and 3 m in depth. The surrounding forest, gradually being restored with beech, ash, maple and fir, adds to the wild atmosphere of the gorge.

• Harrachov (bus station) — blue trail, the so-called Harrachov Road, 7.7 km, 163 m elevation gain, easy — paved path, suitable for prams and wheelchairs
• From the Harrachov glassworks — red trail, alternative route
• From Rýžoviště or the Mining Museum — additional starting points

• Mumlavská bouda, a mountain restaurant, stands right next to the waterfall — a great spot for a break
• The potholes in the riverbed may look inviting in summer, but swimming is dangerous — deep water, smooth walls and strong currents
• The site lies within Krkonoše National Park
• The route is suitable for families, cyclists and wheelchair users

The earliest recorded mention of the waterfall dates to 1804, when traveller J. K. E. Hoser described the river simply as 'Muml' — proof that this hidden gem has been drawing curious visitors for over two centuries.