The passenger steamer SS Warrimoo was quietly knifing its way through the waters of the mid-Pacific on its way from Vancouver to Australia. The navigator had just finished working out a star fix and brought the master, Captain John Phillips, the result. The Warrimoo’s position was latitude 0 degrees x 31 minutes north and longitude 179 degrees x 30 minutes west.
The date was 30 December 1899. Know what this means? First Mate Payton broke in, we’re only a few miles from the intersection of the Equator and the International Date Line.
Captain Phillips was prankish enough to take full advantage of the opportunity for achieving the navigational freak of a lifetime. He called his navigators to the bridge to check and double check the ships position. He changed course slightly so as to bear directly on his mark. Then he adjusted the engine speed. The calm weather and clear night worked in his favour. At midnight the Warrimoo lay on the Equator at exactly the point where it crossed the International Date Line!
The consequences of this bizarre position were many. The forward part of the ship was in the Southern Hemisphere and the middle of summer. The stern was in the Northern Hemisphere and in the middle of winter. The date in the aft part of the ship was 31 December 1899. Forward it was 1 January 1900.
This ship was therefore not only in two different days, two different months, two different seasons and two different years but in two different centuries-all at the same time.
Read more here, on Wikipedia