4464 Bittern is a London and North Eastern Railway Class A4 steam locomotive. Built for the LNER in 1937 at Doncaster Works as works number 1866, it was originally numbered 4464. It was renumbered 19 on 16 August 1946 under the LNER 1946 renumbering scheme and after nationalisation in 1948 BR added 60000 to its number so it became 60019 on 10 October 1948. It is a Pacific 4-6-2 locomotive to the same design by Sir Nigel Gresley as the more famous A4 Mallard and one of the 35 strong class. It is one of six to survive into preservation and is one of two currently certified for mainline use.