Birdcage Walk is a street in the City of Westminster in London. It runs east-west as a continuation of Great George Street, from the crossroads with Horse Guards Road and Storey's Gate, with the Treasury building and the Institution of Mechanical Engineers on the northeast corner, to a junction with Buckingham Gate, at the southeast corner of Buckingham Palace. St. James's Park lies to the north, whilst to the south are the backs of buildings on Old Queen Street, Queen Anne's Gate and Petty France, and, at the western end, the Wellington Barracks of the Brigade of Guards.