Departing from the hamlet of Vareilles, in Ambérieu-en-Bugey, an exceptional walk awaits you. An easy and enchanting part to the blue lake. Then, for the more athletic, a hike to the fabulous ruins of the Château de Saint-Germain. Ready to board? I am taking you !
From the blue lake to the Château de Saint-Germain
Beginning of the trip
45 minutes after my departure from Lyon, I arrive there, armed with my camera. The easiest way to start is to park in front of the park of the castle of the Scales. Already a castle! Yes, but that's not the one I'm exploring today. Next time, without fail.
I who thought I knew Ambérieu-en-Bugey, I quickly realize that this beginning of the walk takes me to a place that is unknown to me: the district of Vareilles. A hamlet which has preserved an authentic and discreet charm but also a calm, almost secret atmosphere.
After a few minutes of walking, I gradually leave the houses and the hamlet behind me to arrive at dawn in the forest. the roach, pretty little stream, still follows my steps. Along the way, explanatory panels present the district and its history.
I continue the path, always straight, and discover a beautiful waterfall. Five minutes of walking later, a pretty wooden bridge overhanging the blue lake takes shape.
The Blue Lake
Here I am arrived at one of the star places of our territory: the blue lake.
It bears its name perfectly. I arrive on a summer morning when the sky is already clear and the water is a beautiful azure blue. This is the magic of the place! The color of the lake varies depending on the day and the lights to go from emerald green to turquoise blue.
But then why this color? In reality, copper mines were exploited along the Gardon stream. It is then the oxidation of copper in contact with water that creates this turquoise blue. That, or a magical effect of course…
The blue lake is a natural environment for walk around and escape. Perfect for taking a break enjoying its quiet atmosphere or just enjoying good local products on the picnic tables, in the middle of the woods. The blue lake is not swimmable.
Finally, it is above all a real paradise, if like me you like to take pictures. It is at sunset that the colors are the most beautiful.
It is time to retrace my steps, descending along the roach. The walk can end here, by taking the same path as on the way out. Unless…
Hike to the castle
The day is beautiful and I feel ready. I decide to continue the trip by taking the hiking trail, about 2 hours in total, which leads to the castle.
Going down from the blue lake, a few hundred meters further, yellow markup begins and tells me to turn left to begin the ascent to the Château Saint-Germain.
Well, without lying, it's still sporty. With a drop of 155 meters and most of the path is small rocks, you have to hang on. It is true that I happened to stop during this ascent, but it was only for admire the forest around me, of course.
The castle of Saint Germain
Finally I arrive at the ruins of the castle. For an enthusiast of old stones like me, what I see is simply exceptional. It only remains for me to get to know this place which I already like…
A very old site
On site, informative panels very complete on the castle and the ruins guide the discovery of the place. In addition, thanks to the numerous excavations carried out, the work of research and digital creation, the castle is now visible in 3D. A veritable mine of information that allows total immersion.
I then learn that archaeological excavations made it possible in the 70s to reveal the presence of a small church and a necropolis dating from the Merovingian period. More exactly from middle of the XNUMXth century. How did they find out? Through dating carbon 14.
And treasures of yesteryear
But ! Of the ceramic shards found during these same excavations show that the site would have been occupied from late 4th or 5th century. Do you realize Jamy! Hmm, hm, sorry.
It's amazing to imagine that these places have been occupied for so long… And that I stick to them too.
It was in the Middle Ages that the castle of Saint Germain is built (it is quoted in texts from 1141). It takes place in a fortified set of 4 hectares and controlled part of the border between Dauphiné and Savoie. This is what gave it great strategic importance during the wars between Dauphiné and Savoy (in the XNUMXth and XNUMXth centuries).
A defensive function
Let's talk about these wars. Whether for the Viennese Dauphins or later the Counts of Savoy, I learn that the castle was above all: a military fortress.
Who says military fortress, says defense and says… Attacks! Two times, the counts of Savoy laid siege to the castle. In 1283, following which it was restored by decree, then in 1321.
On these seats, accounting sources indicate that several machines were mobilized: a trebuchet et a mangonel (who pounded the fortifications with their balls), a cat " (ram intended to break down the door) and a "sow" (a movable wooden siege tower to protect pedestrians during the assault).
The ruins speak
Enough about battles. I reconnect with what I see around me and many parts of remains are to be discovered. Small non-exhaustive tour of the owner.
It's all in the attention to detail.
Namely that the end of the period of habitation of the place corresponds to the transfer of Bresse and Bugey to the King of France Henri IV (by the Duke of Savoy) in 1601. . Quickly dismantled, the vegetation then carried out its work for 400 years.
A very beautiful architecture
I move forward and find myself face to face with: the ogival door. It owes its name to the shape of its opening: a very open pointed pointed arch. I read that it was built when adding a thickness of wall from the outside of the castle in 1325.
Above this door is the big room. Well, what's left of it. That is to say a large wall and boundaries on the ground. Also called class (which led to the word “hall” later), this room had multiple functions: meals, meetings, receptions…
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The great hall (on the left) being reconstructed ![]()
The great hall today
But what is this ignominy?! (I exclaimed suddenly, of course). I see another castle in the distance. One of the knights whispers in my ear that it's good the castle of Allymes ! Also a strategic military and political point, it was, like Saint-Germain, an important point of interest in the Dauphino-Savoyard conflicts.
![château des allymes.]()
The castle of Allymes ![Forêt du château de Saint-Germain]()
The forest around the Château de Saint-Germain ![Panorama sur Ambérieu-en-Bugey depuis le château de Saint-Germain.]()
Panorama of Ambérieu-en-Bugey
The icing on the cake, from the back of the upper courtyard, an impressive panoramic view unfolds over the whole of Ambérieu-en-Bugey and the plain.
I leave you the surprise of discovering the other many points of interest. To finish, just go back down the same path.
It's time to continue our journey without ever forgetting these mysterious blue lake and castle of Saint-Germain 🤫
◼ On the way back
(I.e. Useful information
For all that is roadmap, routes and additional information, everything is available on our website both for the footpath of “Vareilles at Lac Bleu: along the Gardon” and to the hike from Vareilles – blue lake to the castle of St-Germain.
(I.e. Of a curious nature?
And how I understand you! It's normal to want to know more about the secrets and news of these places. The organization " Friends of Blue Lake " and " The Friends of Saint-Germain and its castle can help you quench your thirst for knowledge.
(I.e. Want to stop celebrating on the way back?
- I hasten to recommend you some good inns present in the town of Ambérieu. First of all, Auberge des Allymes, a new address where everything is homemade and with local products of course! It is located at the foot of Allymes castle. Perfect for a smooth disconnect after the leap in time you just took on a ride.
- Going down towards the city center you will find the address of the Bon vivant. A restaurant with modern, original cuisine made from fresh products. And above all, as its name suggests, a place where joy and love of living (and eating, of course!) mingle.
- Finally, for tasty and hearty French cuisine, it's direction The little restaurant. A place where everything is homemade from appetizer to dessert, by Patrice, chef for over 25 years. On the terrace or to take away!
- Bonus: for a lighter snack, I can also recommend the fun bar: Juices and Games. A playful café inspired by the “slowcafé” where you pay for the time spent on site! Unlimited choice of drinks, toy library and self-service library.
◼ Practical information and sources
👉 Do not hesitate to share your photos of your ride on Instagram by identifying us: @perougesbugeytourism
Let's be citizens: let's respect the places. Be careful not to enter the private properties of local residents and not to leave waste.
My sources : Brief history of the Saint-Germain site, Alain Kersuzan. Castle of Saint-Germain in 3D. Telephone interview with Patrice Petit-Roche, president of the “Friends of the Château de Saint-Germain” association.
