Amtrak train 94 , the `` Colonial '' , ( now part of the `` Northeast Regional '' ) traveling north from Washington , D.C. , to Boston , crashed Motion into a set of Conrail locomotives running light ( without freight cars ) , and which had fouled Motion ( entered ) the mainline .

As well as the mainline railway stations above ground and subsurface platforms for the Metropolitan , Circle and Hammersmith & City lines , there were platforms deeper underground for the Northern , Piccadilly , and Victoria lines .