Dungeon guide

This keep in Val-d'Oise, which hides a 100-meter secret passage, reopens its doors

In the heart of the village of La Roche-Guyon, one of Val d'Oise's most beautiful villages in France, an extraordinary troglodyte castle rises, opening to visitors from April 1, 2026, with a medieval keep and its closely guarded secrets.

In Yvelines, you can climb to the top of this tower for a sweeping view of the medieval town.

Rising 25 metres above the Yvelines, Houdan's keep hides a history as solid as it is unusual. A survivor from the 12th century, this stone colossus weathered demolition by being transformed into a functional water tower for nearly a century. An architectural curiosity that today offers an exceptional panorama of the medieval town.

The only medieval keep with buttresses in Île-de-France is located in the Yvelines.

In Yvelines, at Maurepas, the remains of a 20-meter-high cylindrical keep stand as the sole remnant of a medieval fortress from the 12th century. Recognized as a historic monument since 1926, it still holds the secrets of a turbulent past. Here’s the story.

The tallest castle tower in Europe is just outside Paris, within easy reach of the metro!

Did you know that Europe’s tallest medieval tower was just a short ride from Paris, in the heart of a remarkably well-preserved castle? Here’s everything you need to know!

This medieval tower, offering a breathtaking panoramic view of Essonne, was once used to measure the speed of light.

Perched atop a 30-meter-high hill, the Montlhéry Tower offers a breathtaking panoramic view of Essonne and the Île-de-France region. This historic medieval relic, officially listed as a Monument Historique, once served as a laboratory for some of the greatest scientists of the 19th century. Whether you're interested in its history, planning a visit, or just taking a leisurely walk, here's everything you need to know.

This historic keep, the last remaining remnant of a royal castle, may soon reopen its doors to visitors.

The Guinette Tower, the last remaining remnant of Étampes Castle, is at the heart of a restoration project aimed at making the ruins of this medieval fortress accessible to visitors once again. Here's the story of this endangered heritage site.

In Seine-et-Marne, this medieval keep opens its doors to the public during exclusive guided tours.

It is a remnant of a medieval castle in Seine-et-Marne, now a captivating piece of heritage. The Houssoy Keep opens its doors to visitors during special guided tours, offering a unique glimpse into its secrets and history!