Introduction
Welcome to Thun, the gateway to the Bernese Oberland and one of the most dramatically situated towns in Switzerland. Here, the Aare River pours out of Lake Thun in a rush of turquoise water, and the first peaks of the high Alps rear up from the lakeside like a wall of rock and ice. Thun has been the key to the Oberland for a thousand years, and the castle that crowns its hilltop has watched over this strategic junction since the twelfth century.
This walk descends from the castle through the remarkable old town, with its unique elevated pavements and double-decker shopping streets, follows the Aare to the lake, and ends in the gardens of Schadau Park, where the panorama of Lake Thun and the Bernese Alps is one of the most photographed views in Switzerland. Along the way, you will discover a town that combines medieval charm with a vibrant modern culture, and a landscape that has inspired artists, writers, and travellers for centuries.
Stop 1: Schloss Thun — 46.7580, 7.6290
Thun Castle commands the hilltop at the centre of the old town, its massive square keep visible from every direction. The castle was built around 1190 by Duke Berthold V of Zahringen, the same dynasty that founded Bern, Fribourg, and several other Swiss cities. The Zahringers were master urban planners, and their cities share certain design features: regular street grids, defensive positioning, and castle-dominated skylines.
The keep is one of the finest Romanesque secular buildings in Switzerland. Its four corner towers and massive walls of grey limestone create a silhouette that is instantly recognisable. Step inside, and you find yourself in the Knights' Hall, a vast room with a barrel-vaulted ceiling that spans the entire width of the keep. This hall, 18 metres long and 12 metres wide, was the ceremonial centre of the castle, where lords held court, received guests, and administered justice.
The castle museum occupies several floors and tells the history of the Thun region through archaeological finds, weapons, armour, and domestic objects. The top-floor gallery offers a 360-degree panorama that is breathtaking: Lake Thun stretches to the southeast, its surface a mirror of sky and mountain; the Niesen pyramid rises to the south; and the snowy summits of the Eiger, Monch, and Jungfrau are visible to the southeast on clear days.
After the Zahringers died out in 1218, the castle passed to the Counts of Kyburg and then to the Habsburgs before being acquired by Bern in 1384. Bern installed its bailiffs here, and the castle served as the seat of local government for over four centuries.
Stop 2: Castle Church (Stadtkirche) — 46.7576, 7.6293
Adjacent to the castle, the Stadtkirche is one of the oldest churches in the Bernese Oberland. The current building dates primarily from the fourteenth century, but its foundations rest on an earlier Romanesque structure that may date to the tenth century. The church became Reformed during the Reformation in 1528, and its interior was stripped of Catholic imagery in the customary manner.
The churchyard around the building is one of the most atmospheric spots in Thun. Ancient tombstones lean at angles among the grass, and the view from the churchyard wall looks out over the rooftops of the old town to the river and the lake beyond. On summer evenings, the light on the Alpine peaks in the distance turns from white to gold to pink in a display that has been entrancing visitors since the era of the Grand Tour.
The descent from the castle church to the old town below follows a steep cobbled lane flanked by medieval houses. The change in elevation is about thirty metres, and the path switchbacks through archways and past half-hidden courtyards that give tantalising glimpses of the town below.
Stop 3: Obere Hauptgasse — 46.7572, 7.6282
The Obere Hauptgasse is Thun's most distinctive architectural feature and one of the most unusual streets in Switzerland. It is a double-decker shopping street where the ground-floor shops have their entrances at street level, but the first-floor shops are accessed from a separate elevated pavement that runs along the building facades at first-floor height, supported on the roofs of the ground-floor shops below.
This arrangement creates two separate pedestrian levels, each with its own shops and businesses. The lower level is the normal street; the upper level is a continuous terrace that you reach by stairs at either end. Walking along the upper pavement, you are at the same height as the first-floor windows of the buildings, giving you an unusual perspective on the old town and intimate views into the domestic interiors behind the commercial facades.
The origins of this double-decker arrangement are debated. One theory holds that it developed as a way to maximise commercial frontage in a town where space was limited by the steep hillside and the river. Another suggests that the upper pavement was originally a defensive feature, allowing defenders to move along the building facades at an elevated level during attacks. Whatever the origin, the result is unique in Switzerland and creates a shopping experience that is both charming and practical.
Stop 4: Rathausplatz — 46.7570, 7.6275
At the western end of the Obere Hauptgasse, the Rathausplatz opens up as the main square of the old town. The Rathaus, or Town Hall, dates from the sixteenth century and features the arcaded ground floor that is characteristic of Bernese civic architecture. Markets have been held in this square since the medieval period, and on Saturday mornings the tradition continues with stalls selling local produce, cheese, bread, and flowers.
The square is surrounded by buildings that represent several centuries of architectural development, from late Gothic to Baroque to early modern. The Freienhof Hotel, one of the oldest hotels in the Bernese Oberland, occupies a commanding position on the square and has hosted travellers since the seventeenth century. Writers, painters, and mountaineers on their way to the Oberland have stopped here to gather supplies and steele their nerves before heading into the mountains.
From the Rathausplatz, look back up at the castle. The view from below is even more dramatic than the view from above: the keep rises above the old town rooftops like a stone fist, its towers catching the light against the sky.
Stop 5: Muhleplatz and the Aare — 46.7565, 7.6268
Descending from the Rathausplatz to the Aare River, you reach the Muhleplatz, the Mill Square, named for the water mills that once lined the river here. The Aare flows out of Lake Thun with tremendous force, and the drop in elevation as it passes through the town created ideal conditions for powering mills.
The Muhleschleuse, a system of weirs and sluices, controls the water level and flow through the town. The engineering is modern, but the principle is ancient: the Aare's power has been harnessed here since the medieval period, and the mills that once ground grain and fulled cloth were the industrial engines of the local economy.
Stand on the bridge and look upstream. The Aare is an extraordinary colour here, a luminous turquoise that seems almost artificially vivid. This colour is produced by glacial flour, microscopic particles of rock ground to powder by the glaciers of the Bernese Oberland and carried in suspension by the river. The particles scatter light in the blue-green part of the spectrum, creating the distinctive hue that makes the Aare one of the most beautiful rivers in Europe.
Stop 6: Aarequai and the Lower Town — 46.7545, 7.6290
Walking downstream along the Aarequai, you enter the lower town, where the atmosphere changes from medieval to nineteenth-century elegance. The buildings here date from the period when Thun was developing as a fashionable resort and garrison town, and the broad quay with its chestnut trees and benches creates a civilised promenade.
Thun was an important military centre from the late eighteenth century onward. The Swiss military academy was established here in 1819, and the presence of the army brought a distinct character to the town: disciplined, prosperous, and cosmopolitan. Officers from across Switzerland were posted here for training, and many brought their families, contributing to the town's cultural life.
The Aarequai also affords views of the castle from below, framed by the river and the old town. The composition of water, bridges, medieval buildings, and mountain backdrop has been painted and photographed countless times, and it remains one of the most iconic views in the Bernese Oberland.
Stop 7: Lakeshore Transition — 46.7520, 7.6320
As the Aare approaches the lake, the character of the landscape changes. The confined river channel opens into a broad, reedy margin where the river meets the lake. This transition zone is ecologically important, supporting a rich community of waterbirds, fish, and aquatic plants.
Lake Thun is 17 kilometres long and up to 217 metres deep, making it one of the deeper lakes in Switzerland. Its waters are exceptionally clean, fed by glacial streams that drain the highest peaks of the Bernese Oberland. The Niesen, a perfect pyramid of a mountain that rises to 2,362 metres directly across the lake, is the most prominent feature of the southern shore and has been called the Swiss Pyramid for its remarkably regular shape.
Boats operated by the BLS Schifffahrt cruise the lake from April to October, connecting Thun with Spiez, Faulensee, and Interlaken at the far end. A cruise on Lake Thun is one of the great Swiss experiences, offering a constantly changing panorama of mountains, villages, and castles.
Stop 8: Schadau Park — 46.7505, 7.6355
The walk ends in Schadau Park, a magnificent lakeside garden that is one of the finest public parks in the Bernese Oberland. The park occupies a peninsula that juts into the lake, and the Schadau Castle, a nineteenth-century Neo-Gothic fantasy, presides over the grounds.
Schadau Castle was built between 1846 and 1852 in the style of a French chateau, complete with turrets, towers, and an ornamental moat. It was commissioned by a wealthy Bernese businessman as a private residence and is now operated as a restaurant and event venue. The architecture is romantic and theatrical, perfectly suited to its lakeside setting.
The park's gardens are planted with mature trees, including several magnificent cedars and sequoias, and the lawns sweep down to the water's edge. The view from the lakeside is the classic Thun panorama: the lake stretching southeast toward Interlaken, framed by the Niesen on the left and the Stockhorn range on the right, with the distant snow peaks of the Eiger, Monch, and Jungfrau floating on the horizon.
Conclusion
Thun is the doorstep to the Bernese Oberland, but it deserves to be more than a transit point. Its castle, its remarkable double-decker streets, its turquoise river, and its lakeside setting combine to create a town of exceptional character and beauty. Linger here before heading into the mountains. The Alps will wait.
Practical Information
- Best Time: Summer for swimming, lake cruises, and outdoor dining. Autumn for the golden light on the mountains. Winter for the Christmas market in the old town.
- Wear: Good walking shoes for the cobblestones and castle hill. The descent from the castle to the lake involves steps and gradients.
- Bring: Swimwear in summer for the lakeshore swimming areas. A camera for the panoramas.
- Nearby Food: The Obere Hauptgasse and Rathausplatz have excellent restaurants. Try the Lake Thun fish specialties: Felchen (whitefish) and Egli (perch). The Schadau restaurant has lake-view dining.
- Getting There: Direct trains from Bern (20 min), Interlaken (25 min), and Zurich (80 min).