Altreu: Boat Trip from Solothurn to Switzerland’s Stork Village

Just a few kilometres downstream from Solothurn, the Aare slows down, the banks turn green and wild, and the rooftops of a tiny hamlet suddenly fill up with enormous nests. This is Altreu, Switzerland’s stork village, and one of my favourite half-day trips from my hometown. The best way to get there is the slow way: by boat down the Aare, with lunch on the riverside terrace of the Restaurant zum Grüene Aff before you head back.

In this guide I’ll cover everything you need: the story of Altreu and its storks, how the boat trip from Solothurn to Altreu and back works (with the times that actually fit together), what to expect at the Grüene Aff, and a few ideas to round off the day.

Quick Facts: Altreu

• Where: On the north bank of the Aare, about 7 km west of Solothurn, part of the municipality of Selzach
• Known for: The Altreu stork colony, founded in 1948 and named a European Stork Village by the EuroNatur foundation in 2008
• Best time for storks: April to August, when more than 40 pairs raise their young
• Boat from Solothurn: About 40 minutes on the Aare boat to Biel, early May to early October
• Where to eat: Restaurant zum Grüene Aff, right on the river, with a huge terrace
• Other ways there: Walk or cycle along the Aare from Solothurn, or take the bus from Grenchen station

Altreu: A Lost Medieval Town That Became a Stork Village

Today Altreu is a handful of houses, a restaurant and a boat landing. It’s hard to believe that this was once a real town. The Romans already had a fort and a bridge here, where their roads crossed the Aare. Around 1260, the noble family of Neuenburg-Strassberg built a fortified little town on the same spot, complete with walls, trenches, a castle and a wooden bridge over the river.

That town did not last long. In 1375, the Gugler, an invading army of mercenaries, destroyed both the town and its bridge. Because the Aare kept eating into the banks, Altreu was never rebuilt. A few years later, the area passed to Solothurn, and Altreu slowly became what it is today: a quiet farming hamlet on the river. In 1831 it lost the last of its independence and became part of Selzach.

The Storks of Altreu

The reason most people come to Altreu today has long legs and a red beak. By the middle of the 20th century, the white stork had disappeared as a breeding bird in Switzerland. Max Bloesch, a gymnastics teacher from Solothurn, decided to bring it back. In 1948 he started his first attempt in Altreu with storks from Alsace, but the real breakthrough only came at the end of the 1950s, when around 300 storks from Algeria arrived.

From Altreu, Bloesch built up a network of 22 satellite stations across the Swiss lowlands, which earned him the nickname “Storchenvater”, the stork father. The University of Bern gave him an honorary doctorate in 1983. Thanks to his work, storks are once again a familiar sight in many parts of Switzerland, and Altreu is still the place where it all started. In 2008, the EuroNatur foundation named it a European Stork Village.

When to See the Storks

The best time to visit is between April and August. In spring and summer, more than 40 stork pairs raise their young in Altreu, and the nests sit on rooftops, chimneys and poles all around the hamlet. You can watch the parents fly in with food, hear the typical clattering of their beaks and, if you are lucky, see the young storks trying their first wobbly flights. A pair of binoculars makes the visit even better.

The Witi Nature Reserve and Info Centre

The storks hunt in the Witi, a wide, flat protection zone of meadows and wetlands along the Aare between Solothurn and Grenchen. It’s also an important resting place for many other birds. The Info Centre Witi in Altreu explains the history of the stork colony and the landscape around it with a permanent exhibition and changing special exhibitions. It’s a good stop if you’re travelling with kids or want to understand what you’re seeing. Check their website for current opening times.

By Boat from Solothurn to Altreu and Back

The boat trip on the Aare between Solothurn and Biel is often called the most beautiful river journey in Switzerland, and the first part to Altreu is a perfect taste of it. The boats are run by the Bielersee Schifffahrtsgesellschaft (BSG) and leave from the Schifflände landing stage on the Aare, right at the edge of Solothurn’s old town. For the whole route to Biel, the ships and all the theme cruises, see my complete guide to the Aare boat from Solothurn to Biel.

From Solothurn, the boat glides past the old town walls, under the bridges and out into the countryside. After about 40 minutes you reach Altreu. On the way you pass reed banks, fields and the Witi, and with the Jura mountains in the background it feels a lot further from the city than it actually is. Keep your eyes open: you’ll often see the first storks and herons before you even arrive.

Timetable: The Best Connections There and Back

The Aare boats run in the summer season, from early May to early October (in 2026 from 2 May to 4 October). These are the times from the 2026 summer timetable that are useful for a trip to Altreu:

My recommended plan: take the 09:00 boat from Solothurn, arrive in Altreu at 09:40, walk around the stork village and the Witi in the morning, have lunch at the Grüene Aff, and take the 14:45 boat back to arrive in Solothurn at 15:25. This combination runs every day of the season, including Mondays, and gives you plenty of time without rushing.

If you only want a quick lunch trip, the 12:40 boat gets you to Altreu at 13:20, and you can still catch the 14:45 back. On Wednesdays, there’s also an evening boat at 19:00, which is a lovely way to have dinner on the river and sail back to Solothurn as it gets dark.

Tickets and Prices

You can buy tickets on board or in advance from the Bielersee Schifffahrtsgesellschaft. The Swiss Half Fare Card and the GA travelcard are valid on the boat, which makes this trip a great deal if you already have one. Since the short stretch to Altreu costs much less than the full ride to Biel, check the BSG website for the current fare for your route. On sunny summer weekends the boats can get busy, so be at the landing stage a few minutes early.

Outside the Boat Season

From October to April there are no boats, but Altreu is still easy to reach. The classic alternative is the walk along the Aare from Solothurn, which takes around two hours on flat paths through the Witi. It’s also a beautiful bike ride. If you’re short on time, there’s a bus from Grenchen station. A popular combination in summer is to walk or cycle one way and take the boat back.

Lunch at the Restaurant zum Grüene Aff

Right next to the boat landing in Altreu is the Restaurant zum Grüene Aff, the “Green Monkey”. For many people from Solothurn, a trip to Altreu without a stop here simply doesn’t count. The big attraction is the terrace on the riverbank: it has room for up to 400 guests, and you sit right by the Aare, watching the boats come in and the storks circling above. Inside, there’s space for around 80 people, which is good to know when the weather turns.

Why Is It Called the “Green Monkey”?

The name comes with one of the best stories in the region. The inn received its licence from Solothurn in 1687. According to the restaurant, a travelling merchant once arrived with a small monkey, probably brought from North Africa via Spain. The innkeeper fell in love with the animal, and after two days of generous hospitality the merchant couldn’t pay his bill, so the monkey stayed. Sadly, it died soon after. The heartbroken innkeeper had a copper figure of his monkey made and put it up outside the inn. Over the years, the copper turned green, and the inn has been “zum Grüene Aff” ever since.

What to Eat

The menu is a mix of local specialities, classic Swiss dishes and modern takes on old favourites, with a seasonal summer menu, mussels and a long list of ice cream coupes and desserts for afterwards. The kitchen stays open all day, which is perfect if your boat arrives at an unusual time. It’s a relaxed, family-friendly place rather than a fine dining restaurant, and that’s exactly what you want after a morning with the storks.

On my visit I went for the cordon bleu with fries, the Swiss classic of breaded meat filled with ham and cheese. It’s a big, hearty plate, and eating it on the terrace with a view of the Aare is hard to beat.

On sunny weekends, the Grüene Aff gets very busy with boat passengers, cyclists and hikers all arriving at once. If you want a table at lunchtime, it’s worth reserving on their website, especially if you need to catch the 14:45 boat back.

More Things to Do Around Altreu

• Take the ferry to Leuzigen. A small ferry crosses the Aare between Altreu and Leuzigen on the other side of the river. It’s a fun little ride and connects to walking and cycling routes on the south bank.
• Continue to Büren an der Aare. If you’re not in a hurry, stay on the boat past Altreu to the historic little town of Büren an der Aare with its wooden bridge, or go all the way to Biel through the lock at Port. The full trip from Solothurn to Biel takes about 2 hours 45 minutes.
• Swim in the Aare. On hot summer days, the river is part of life here. Read my guide to swimming in the Aare before you jump in.
• Add some art. On the other side of the Aare, in the Bucheggberg, the Alte Brennerei Unterramsern shows Swiss art in a former potato distillery.

Make a Day of It in Solothurn

Back in Solothurn at 15:25, you still have the whole afternoon and evening in town. Walk through the baroque old town with my Solothurn travel guide, and for dinner, pick one of the places from my guide to the best restaurants in Solothurn. If you’re planning your visit around a festival, my Solothurn events calendar has every big date of the year. For more ideas across the country, see all my Switzerland guides.

Frequently Asked Questions

Final Thoughts

Altreu is one of those places that shows how close beautiful nature is to Solothurn. In less than an hour on the Aare, you go from a baroque old town to a hamlet full of storks, and you can be back in the city by mid-afternoon. Add a long lunch on the terrace of the Grüene Aff and you have one of the most relaxing summer days the region has to offer. If you’re visiting Solothurn between May and early October, put this trip on your list.