The middle berth exists only in three-tier coaches. During the day it stays folded so the lower berth can be used as a seat by everyone in the bay; the rule is that it may be opened for sleeping only between 10 pm and 6 am, and a passenger who wants it down outside those hours has no right to insist. Inside those hours the lower-berth passenger has no right to keep it up.
It is the berth most often argued over on board and the one the railway’s own rule on sleeping hours is written for. It is also the hardest to climb into and out of, which is why it is the last to be chosen when a preference is offered.
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