Cranscoll Cathedral is a location in Layton Mystery Detective Agency: Kat's Mystery-Solving Files, mentioned in File 34 and fully appearing in File 35. It is a large cathedral in Southampton, built by Earl Dellendar. The accepted story is that the Earl fell severely ill and expecting his death, awakened to faith in God and built the cathedral. When Professor Layton is on his journey to solve the mystery of the Hidden Relics, he discovers that the Earl expanded the cathedral in coorperation with the detective Rufus Aldebaran, who used it as a hiding place for the Relics.
During the events of Professor Layton and the Relics Treasure: Episode 4, the professor and Luke come to the cathedral believing it to be the key location for solving the Relics mystery. When they confront the priest with their knowledge about the Relics, the priest let himself no choice but capturing Layton and Luke.
Eleven years later, Katrielle Layton, Ernest Greeves and Sherl come to the cathedral as well, because Katrielle believes it is the place where her missing father is. Like the professor they also confronts the priest about the Relics, but this time they are prepared for the danger and are accompanied by Chief Inspector Royall Britannias together with a corpse of local police cops. When the priest let his men attack, the cops appear and overpower the priest and his men. Katrielle, Ernest, Sherl and Inspector Britannias then go downwards to the basement where they found the Relics and the professor and Luke, who have been there since their arrival at the cathedral eleven years ago. They are asleep inside coffins that serve as a door to the future.
Spoilers end here