Horse Guards Road  Horse Guards' Road (or just Horse Guards) is a road in the City of Westminster, London. It runs south from The Mall down to Birdcage Walk, roughly parallel with Whitehall and Parliament Street. To the west of the road is St James's Park and to the east are various government buildings, including the Horse Guards building, the Old Admiralty Buildings, the Cabinet Office, Downing Street (the entrance to which is blocked by an iron gate), the Foreign and Commonwealth Office, and HM Treasury. Also to the east is a large courtyard, Horse Guards Parade, where the annual Trooping the Colour ceremony is held in the presence of the reigning monarch.