Thomas, Thomas & Friends, Toys, Construction, Build, Collect, Sodor, Railway, Engines, Blocks, Percy, James, Characters, Show, Buildable, Adventure, Tank Engine, Blue Engine. Build up a royal treasure-finding adventure with Thomas and friends at Ulfstead Castle! It's a perfect day for some fortress fun when your little Thomas fan chuffs out to Sodor's ancient keep! Build up a day of fun with this buildable Ulfstead Castle and help kingly Thomas puff through to find its treasure! Made just for little hands, this easy-to-build set features a special buildable Thomas with King of the castle decorations, a treasure chest, regal turrets and a handy storage bag. Ideal for ages 1 to 5