The Mullerthal is Luxembourg's great natural secret: an area of enchanted forests, streams running through ferns and spectacular sandstone walls carved by millions of years of erosion. It's called 'Luxembourg's Little Switzerland' for its rugged terrain and fairy-tale landscapes, and it's one of those places you don't expect to find in such a small country. There are no big mountains here, but there are narrow gorges, moss-covered rock faces, caves and waterfalls that look straight out of a Brothers Grimm forest.
The heart of the region is the Mullerthal Trail, a 112-kilometre network of paths split into three routes that cross the best of the area. It has been awarded the European 'Leading Quality Trails - Best of Europe' label and is one of the top hiking destinations in the Benelux. Highlights include the romantic Schiessentümpel waterfall, with its little stone bridge; the impressive rock formations of Berdorf; and crevices so narrow and dark you have to squeeze through sideways with a torch.
This guide covers the Mullerthal with a practical eye: the must-do routes and sights, how to get there (by bus, for free) and get around, where to stay and what to combine it with, from nearby villages and castles such as Beaufort and Larochette to historic Echternach. Since 2022, the whole area has been a UNESCO Global Geopark. If you love walking, breathing in the forest and discovering corners where water and rock tell the story of the Earth, you'll fall in love with the Mullerthal.
The Mullerthal landscape is, above all, a geological story: around 200 million years ago, in the Jurassic period, this area was covered by a tropical sea whose sediments formed thick layers of Luxembourg sandstone (Luxemburger Sandstein). Over time, water, ice and streams carved that soft rock into gorges, crevices, caves and colossal blocks, creating the maze-like terrain we admire today. The area has been inhabited since prehistoric and Roman times, but its fame as a nature destination began in the 19th century, when hikers and painters 'discovered' these landscapes and gave them the nickname 'Little Switzerland'. In 2022, UNESCO recognised its geological value by declaring it the Mëllerdall Global Geopark. We tell the whole story on our history page.
Read the full history ↓The 'Little Switzerland of Luxembourg' in the east: forests and sandstone formations crossed by the Mullerthal Trail, with Echternach, the oldest town in the country, its Abbey of Saint Willibrord and its UNESCO-listed dancing procession.
Read the history of Mullerthal Region (Little Switzerland) →A local guide tells you in half an hour what no sign at the site will ever explain. We look ours up on Civitatis: guided in Spanish and booked online with no fuss. They have 9 activities in Mullerthal. And there are free tours here: you book without paying and tip the guide whatever you think at the end, so trying one costs you nothing. Have a look below: tap any of them to see them all.
If you book from here we earn a commission and you pay no more. Prices and availability come from Civitatis.
No exact prices: a scale from $ (budget) to $$$$$ (luxury), with 2-3 options per category.
Origins, formation and what the sources say.
To understand the Mullerthal, you have to go a long way back in time: about 200 million years, to the Jurassic period. Back then, much of what is now Luxembourg lay under a warm, shallow sea. It was a tropical sea, and on its floor grains of sand carried in by rivers piled up layer upon layer. Over thousands of years, under the weight of the sediment, that sand was compacted and cemented into a distinctive rock: Luxembourg Sandstone (Luxemburger Sandstein). In some places this bed of stone is a hundred metres thick.
Luxembourg Sandstone has one feature that is key to the landscape we see today. It is a fairly soft, porous rock that water wears away easily. When the sea withdrew and the region rose above the water, a very slow process of natural sculpting began. Rivers and streams such as the Sûre, the Black Ernz and the White Ernz cut down into the rock. Rainwater seeped into the cracks, dissolving the stone and breaking blocks loose.
That marine origin explains the most curious details of the terrain. In the stone you can find fossilised ripple marks left by ancient waves and the remains of sea creatures. At heart, the Mullerthal is the bed of a vanished sea. It was lifted up and carved over geological ages until it became the maze of rock and forest that hikers explore today.
The Mullerthal's spectacular terrain is mainly the work of water and ice. Over the last few million years, and especially during the Quaternary ice ages, cycles of freezing and thawing opened fractures in the sandstone. Water seeped into the cracks, froze, expanded and split the rock, and then streams carried the loose pieces away. Block by block, this formed narrow gorges, sheer walls and crevices so tight that today you have to squeeze through them sideways with a torch.
That is how the area's most famous spots came about. There are crevices like the Kuelscheier, ravines like the Wollefsschlucht ('wolves' gorge'), huge blocks separated by passageways, and small caves and rock shelters. The Schiessentümpel waterfall, with its three cascades, shows the same process in action: the stream wearing away the stone step by step.
A lush and very particular plant life took hold on this damp, shady rock. Beech woods, ferns, mosses and lichens cover the walls and give the trails their enchanted-forest feel. Soft sandstone, plenty of water and a humid climate combined to create an ecosystem so unusual that it is now protected. There is hardly anything else like it in a small, largely flat country like Luxembourg.
People came to these valleys early. The Mullerthal's rock shelters and caves offered natural refuge, and there are signs of human presence going back to prehistoric times. Later, in the Roman era, the region belonged to the territory of the wealthy Augusta Treverorum (today's Trier, in Germany), one of the Empire's great cities in the north. A large Roman villa stood near Echternach, and roads and rural settlements crossed the area.
Through the Middle Ages and the early modern period, the Mullerthal was a land of forests, small villages and, above all, mills. The name says it all: 'Mullerthal' is German for 'valley of the mills' (from Müller, miller). The streams drove the wheels of many flour mills and other mills, and for centuries these were the economic engine of the valleys. The village of Mullerthal, which gives its name to the whole region, keeps that memory alive in its name.
The forest was another key resource, providing timber and game. In Berdorf, millstones were also cut straight out of the sandstone. The old Hohllay quarry is a reminder of this, and today it is an unusual natural amphitheatre carved into the rock. It was a hard, quiet rural economy, still far from the tourist fame that would come later.
The Mullerthal's fortunes changed in the 19th century. This was the age of Romanticism, when travelling in search of 'wild', picturesque and sublime landscapes became fashionable all over Europe. Hikers, painters and writers began exploring these valleys and were captivated by the gorges, the moss-covered rocks and the shady forests. It was then that someone came up with the nickname that would stick: 'Luxembourg's Little Switzerland' (Petite Suisse, Kleng Lëtzebuerger Schwäiz), comparing this rugged terrain to Alpine scenery.
The name was more poetic than geological, since there are no mountains or glaciers here. Even so, it caught on and drew the first tourists. Paths were opened, routes were waymarked and some hotels began taking in visitors. Being close to Germany and the city of Trier helped bring hikers in, and later so did the railway to Echternach. By the 19th and early 20th centuries, the Mullerthal had become one of the country's first nature destinations.
That Romantic outlook laid the foundations for what the region is today: a place valued for its natural beauty rather than its mills or timber. The idea of protecting and showing off the landscape, rather than exploiting it, was born back then.
In recent decades, the Mullerthal has fully embraced high-quality nature tourism. The big milestone was the creation of the Mullerthal Trail, a 112-kilometre network of paths split into three circular routes that link the best of the region. Along the way are the rocks of Berdorf, the Schiessentümpel waterfall, the crevices and gorges, the villages and the castles of Beaufort and Larochette. The trail has earned the prestigious European 'Leading Quality Trails - Best of Europe' label, which recognises the continent's best hiking routes. It has made the region a benchmark for hiking in the Benelux.
Alongside the trail, the Natur- & Geopark Mëllerdall was set up as a nature park focused on protecting the area's geological heritage and explaining it to the public. Its biggest recognition came in 2022, when Unesco added it to the Global Geoparks network. The label honours both the exceptional geological interest of Luxembourg Sandstone and the conservation and education work built around it.
Today the Mullerthal brings all of this together. It has a landscape that reads like an open book of 200 million years of Earth's history, a dense network of first-class trails, quiet villages and romantic castles. Next door is Echternach, with its heritage going back more than a thousand years. From the bed of a Jurassic sea to a Global Geopark, 'Luxembourg's Little Switzerland' shows that the most surprising landscapes are sometimes hidden in the smallest countries.
