High Quality Content by WIKIPEDIA articles! The New Bus for London, sometimes referred to as NB4L, and colloquially as the New Routemaster, Borismaster or Boris Bus (named after the Mayor of London who introduced them, Boris Johnson) is a 21st century replacement of the iconic Routemaster as a bus built specifically for use in London. Designed by Heatherwick Studio, it is built by Wrightbus, and features the `hop-on hop-off` rear open platform of the original Routemaster, but meets the requirements for modern buses to be fully accessible. The first bus entered service on 27 February 2012.