Have you heard? No, you’re not dreaming! It’s the chilling breath of Halloween that’s returning to haunt Paris and the Île-de-France... And it doesn’t spare the Val-d'Oise (95)! On Saturday, October 31, 2026, the Château de Grouchy, a splendid 18th-century residence set in a 42-hectare park in Osny, will transform into a theater of fright where mystery, chills and whimsy join the party.
From 2 p.m., the festivities kick off with a pumpkin contest open to all ages and pumpkin-art enthusiasts. From 3 p.m., the little ones are whisked away to a realm of wonder with a session of children's stories, a gentle thrill before night falls.
When darkness settles over the park, the castle reveals its most unsettling face... From 7 p.m., the bravest will step into the formidable parcours hanté immersif (for ages 8 and up). The villains from our childhood stories seem to have stepped out of the books to scare us. A journey through shadows and whispers, where every step promises an adrenaline rush... and a few nervous laughs.
Fortunately, at the end of this journey, there’s something to comfort you: pumpkin soup and candy, a perfect Halloween menu! Of course, there’s no question of celebrating this holiday without donning an appropriate look. Go all out with your costumes and enter the photo contest at a decorated booth!
The event is open to all the brave, reservation required. So, don your scariest costumes and come experience a spellbinding Halloween night in the historic backdrop of the Château de Grouchy.
Dates and Opening Time
On October 31, 2026
Location
Grouchy Castle
14 Rue William Thornley
95520 Osny
Route planner
Prices
Contes: €4
Parcours hanté: €7
Recommended age
From 8 to 99 years old
Official website
osny.fr
