B777 have an underfloor cabin crew rest area. It is the size of a double LD3 at the front of the rear freight hold. It is accessed by a near vertical ladder from a toilet sized compatment by R3
door. It can be removed like a container, and it has happened that the loaders ripped one out once by mistake, so inside the freight hold it is covered in large wording to stop them doing this! The pilots have two bunks just aft of the cockpit on the port side on the main deck.