London's iconic double-decker bus at Marble Arch and Hyde Park. The New Routemaster, originally referred to as the New Bus for London and popularly known as the Boris Bus or Borismaster (a portmanteau of the name of the former Mayor of London, Boris Johnson, who drove their introduction, and that of the AEC Routemaster that they were designed to replace) is a hybrid diesel-electric double-decker bus operated in London. Designed by Heatherwick Studio, it is manufactured by Wrightbus, and is notable for featuring a "hop-on hop-off" rear open platform similar to the original Routemaster bus design but updated to meet requirements for modern buses to be fully accessible. The first bus entered service on 27 February 2012.