Euston was the first inter-city railway terminal in London, planned by George and Robert Stephenson. The original station was designed by Philip Hardwick and built by William Cubitt, with a distinctive arch over the station entrance. The station opened as the terminus of the London and Birmingham Railway (L&BR) on 20 July 1837. Euston was expanded after the L&BR was amalgamated with other companies to form the London and North Western Railway, leading to the original sheds being replaced by the Great Hall in 1849. Capacity was increased throughout the 19th century from two platforms to fifteen. The station was controversially rebuilt in the mid-1960s, including the demolition of the Arch and the Great Hall, to accommodate the electrified West Coast Main Line, and the revamped station still attracts criticism over its architecture. Euston is to be the London terminus for the planned High Speed 2 railway and the station is being redeveloped to handle it.