 It quickly grew to cater for suburban lines and was expanded several times in the 19th century.It came under the ownership of the London and North Eastern Railway as part of the Big Four grouping in 1923, who introduced famous services such as the Flying Scotsman and locomotives such as "Mallard".The station complex was redeveloped in the 1970s, simplifying the layout and providing electric suburban services, and it became a major terminus for the high-speed InterCity 125. , long-distance trains from King's Cross are run by London North Eastern Railway to , and ; other long-distance operators include Hull Trains and Grand Central.