Five on a Hike Together by Enid Blyton

The Famous Five—Julian, Dick, Anne, George, and Timmy the dog—set off on a hiking trip during the school holidays. When Dick receives a strange message meant for someone else, they find themselves caught up in a mystery involving a hidden treasure. As they explore moorlands, old houses, and secret locations, danger follows close behind. They must piece together clues, avoid suspicious characters, and stay one step ahead. This story combines outdoor adventure with a suspenseful treasure hunt.