Tile; Way out niche sign, from eastbound Piccadilly Line platform at Green Park station, circa 1907

In early designs for Underground stations, glazed tiles were used both inside and out to provide a durable, high-quality finish. This 'Way Out' niche sign comes from the Piccadilly line platform at Green Park station. Curved to follow the profile of the tunnel, the sign is made up of different coloured tiles and depicts the outline of the ticket office windows in the booking hall above. Architect Leslie Green was commissioned by the Underground Electric Railways Company of London (U.E.R.L.) to create a unified style for the Underground.