Here are 10 things you might not know about cruise ships. Part of our Did You Know series.

Here are 10 things you might not know about cruise ships:

1st purpose built cruise ship was the Prinzessin Victoria Luise launched in 1900;

2 metres - the length that Harmony of the Seas is longer than its sister ship Allure of the Seas, making it the longest cruise ship in the world at 362 metres;

6 minutes 25 seconds – the world record time for water skiing behind a cruise ship at 14 knots;

10.1 metres – RMS Queen Mary 2’s draught depth, the world’s largest ocean liner;

44 tonnes - weight of the largest life boats used on cruise ships, capable of carrying 370 people;

450 cruise ship calls in Southampton during 2015, making it the busiest cruise port in Europe; 

770 metres - the length of Queen Mary 2’s anchor chains; 

3,300 miles of electrical cables used in Oasis of the Seas;

8,500 passengers and crew capacity on board Harmony of the Seas;

226,963 gross tonnes – the weight of Harmony of the Seas, the heaviest cruise ship in the world.

^{Further information}

^{Cruise International}

^{Cruise Market Watch}

^{Cruise Mapper}

^{Cunard [archived]}

^{Ship Technology}

^{The Guardian}