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

While the Paris region is filled with iconic landmarks, there are hidden gems within our heritage that remain largely unknown, revealing themselves only to the most dedicated explorers. These adventurers are rewarded with rare and exceptional visits, gaining the satisfaction of uncovering these still-secret sites that are, despite their hidden nature, steeped in history.

Remnant of an ancient fortress, the Houssoy Keep stands out among the region’s hidden gems. Nestled in the heart of the Ourcq Valley in the town of Crouy-sur-Ourcq, in Seine-et-Marne. Its origins date back to around 1390, during the Hundred Years’ War, and it remains one of the few medieval keeps still standing in the area today.

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But be warned, the Houssoy Keep isn’t open for visits all year round. It’s important to check ahead for upcoming special tour dates. These events usually take place once a month on a Sunday, and access is by reservation only (link right here). When you attend, you’ll get to marvel at the stunning architecture of this square tower, along with its suspended chimneys—an impressive showcase of the craftsmanship behind this historic structure. It’s also a perfect opportunity to step back in time and explore the history and evolution of this medieval site that takes you in the footsteps of the Counts of Valois.

During this guided tour, you'll explore the keep across multiple floors, so it's recommended to wear comfortable clothing to fully enjoy the experience. Please note, the site is not accessible to visitors with mobility impairments. The entry fee for adults is €7, but children can tour for free!