Known as The Nightmare Realm, the multi-award-winning event will open at the Avery Hill Mansion for 18 nights from October 9 to November 1, 2026. The Nightmare Realm has developed a reputation for its unusual brand of horror storytelling and theatrical performance. In 2026, The Nightmare Realm celebrates its 17th year, having commenced in Ireland back in 2009. A multiple winner of Best Halloween Event in Europe at the ScareTOUR Awards, The Nightmare Realm has proved itself as an impressive horror experience. With the introduction of The Nightmare Realm to the UK, October promises to be a delightful treat of fear and thrill for all horror enthusiasts.