English: Waterloo & City line train towards Bank calling at Waterloo station. The Waterloo and City line opened in 1898 and is the shortest line on the network, having only two stations - Waterloo and Bank. It is also one of only two lines to be entirely underground, the other being the Victoria line. It was part of the British Rail network until 1994, when operation was transferred to London Underground. Since 2010 it has been the only London Underground line to use 4 coach trains. It is intended for commuters who have their workplaces in the City of London, and for this reason it does not operate on Sundays or public holidays except in exceptional circumstances (e.g. in 2012 during the Summer Olympics). It is currently operated by 1992 Stock, which was introduced in 1993 and is also used on the Central line (though unlike Central line trains, Waterloo and City line trains do not feature ATO).