The iconic "Routemaster" double-decker buses are among the most well known British icons. They were delivered between 1954 and 1968 and remained in regular service until December 2005. These buses were retired due to the fact they required a conductor to monitor the open, rear platform and were not accessible to those in wheelchairs. Following their removal from regular service, two "heritage routes" were started to keep them in service, primarily as a tourist attraction. One of these routes was discontinued in 2014. The second route saw its hours significantly cut back in 2019 before service was suspended entirely during the Covid-19 pandemic. In April of 2021, it was announced that this heritage route would not return to service. An updated Routemaster model, officially known as the "New Routemaster", entered service in February 2012.