Trafalgar Square is owned by the Queen in Right of the Crown and managed by the Greater London Authority, while Westminster City Council owns the roads around the square, including the pedestrianised area of the North Terrace. The square contains a large central area with roadways on three sides and a terrace to the north, in front of the National Gallery. The roads around the square form part of the A4, a major road running west of the City of London. Originally having roadways on all four sides, traffic travelled in both directions around the square until a one-way clockwise gyratory system was introduced on 26 April 1926. Works completed in 2003 reduced the width of the roads and closed the northern side to traffic.