Cityflyer is an airport coach service to Hong Kong International Airport and Hong Kong-Zhuhai-Macau Bridge provided by Citybus. The service was started during the opening of the Hong Kong International Airport in 1998. Fleet At the time of the opening of Hong Kong International Airport in 1998, the fleet consisted of 62 Dennis Trident 3 double decker buses (fleet numbers 2100-2161), of which 11 had Alexander ALX500 bodies and the other 51 had Duple Metsec DM5000 bodies. Ten MAN NL262/R single deckers (fleet number 1560 - 1569) were added to the fleet in 2006 for use in route A10. Two urban-specification Alexander Dennis Enviro500s (8203-8204) joined the fleet in 2011, and were repainted with Cityflyer livery but retained their normal seats which differ from the high backed coach seats of the other buses. They were returned to normal Citybus livery in 2013. Another three urban-specification buses (8205-8207) joined the fleet in 2012 with a modified version of the Cityflyer livery as reserves to cover for unavailable coach-specification buses, and these 3 buses moved to non-franchise fleet in 2020 for private hire or special services. From 2013 to 2014, the Dennis Tridents were replaced by 66 new 12.0 metre Enviro500 MMC buses (8000-8065). The MAN NL262/R were withdrawn in 2016, and subsequently replaced by the 12.0 metre Enviro500 MMC. Longer 12.8 metre Enviro500 MMC (6800-6811) were ordered soon after the 12.0m order. Further orders of the 12.8m Enviro500 MMC (6812-6843) were delivered in 2017–2018 to cope with rising passenger numbers on existing routes and the added passenger flows from the Hong Kong-Zhuhai-Macao Bridge. A further batch of 28 (6844-6871) were delivered in 2019-2020. All Cityflyer routes with the exception of A10, A17, A23 and NA10 have been cleared to use the 12.8 metre (42 ft) long buses. Currently, the fleet consists of 138 Enviro500 MMCs including 66 12m and 72 12.8m vehicles. Routes Cityflyer operates Airport Routes A10, A11, A12, A17, A20, A21, A22, A23, A26, A29 and A29P, as well as overnight routes NA10, NA11, NA12, NA20, NA21 and NA29. The Cityflyer service is an indirect rival to the Long Win Bus service provided by Kowloon Motor Bus, which operates in the New Territories (excluding Sai Kung). On 28 November 2005, the Transport Department (TD) of Hong Kong invited tenders for new airport route plying between Hong Kong Southern District and Airport via Mount Davis Road and Kennedy Town. On