CityBus is one of the three major bus operators in Hong Kong, it provides both franchised and non-franchised bus services. The franchised route network serves mainly Hong Kong Island, cross-harbour routes (between Hong Kong Island and Kowloon/New Territories), Ocean Park, North Lantau (Tung Chung and Hong Kong Disneyland) and Hong Kong International Airport. The non-franchised routes serve mainly City One Shatin.

When the new Hong Kong International Airport opened on 6th July 1998, Citybus introduced a network of routes using the CityFlyer brand name, to connect the new airport with Hong Kong Island and Kowloon. Fleet No 2201 is one of over 150 Duple Metsec bodied Tridents purchased to cater for these extra services. It entered service on 23 December 1998.