High Quality Content by WIKIPEDIA articles! Articulated buses, popularly called bendy buses, were introduced to London in June 2002 when the then Mayor of London, Ken Livingstone, introduced new Mercedes-Benz Citaros to Red Arrow commuter services 507 and 521. While articulated bus operation had been standard in several other countries, the UK had only sparingly tried their use, so their introduction in London caused a lot of press attention.