What: http://hiddenvalleydiscoverypark.co.uk “The must puzzliest place in Cornwall” Where: Tredidon, Launceston PL15 8SJ They say: Hidden Valley opened in 1994, with a garden shed in the field, with a Scavenger trail and a small display of chocolate bars for sale, a small woodland play area soon saw a tea room and array of tin sheds, garden railway, cottage, telephone box and walk in mine tunnel. A few years later saw the introduction of the Vault and a miniature railway taki