I have a Cadbury's free ticket voucher, how do I pre-book? You will need to pre-book a ticket to guarantee entry, please do so here. Please bring your pre-booked ticket and your Cadbury pack voucher to gain entry at the turnstiles. Related articles I have a promotional offer, how do I use this online? I have a Kellogg’s snack pack voucher (e.g Fruit Winders, Rice Krispie Squares), how do I pre-book my ticket? I have a Sun 2 4 1 voucher, how do I pre-book? What are your opening times? As a Merlin or Thorpe Annual Passholder, how do I reserve my entry ticket?