From October 1 to November 1, 2026, Sherwood Parc, France’s largest adventure park, turns into Halloween country in Viarmes, Val-d’Oise. On October 24, 29, 30 and 31, enjoy family-friendly daytime activities and four evening sessions from 5 p.m. to 10 p.m. Monsters in the woods, shows, face painting, and sweets will pace these gatherings. When night falls, the nocturnal accrobranche and a 500-meter haunted trail set a chilling medieval mood.