The huge plan, regarded as the Holy Grail of Titanic memorabilia, shows the intricate detail of the ship - from the location of the squash court, to the Turkish baths to the first-class lavatories.

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Carnival has not requested assistance from the Coast Guard, which has no jurisdiction in the ship's current location, Coast Guard Petty Officer Jon-Paul Rios told CNN.

CNN: STORY HIGHLIGHTS

Its location gave them refuge from the northern sea storms and access to the ship building materials found in Ireland's dense forest.

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