Buy Santas Grotto @ Ardgillan Castle vouchers for deals on Santa's Experience Entry. Ticketing Options: Dublin’s Ardgillan Castle plays host to a grotto tour, which will be available until 23 December. Greeted by Santa’s butler, guests will be guided through Christmas traditions and types of gifts popular in the past. Children will be able to write a letter to Mr. Claus and post it to the North Pole, see his stylish carriage, and the elves. A magician and, as rumour has it, Rudolf the Rednosed Reindeer will also be on the spot, as well as a photographer, ready to document the experience. Each child will also receive a gift.