When double-decker buses were first introduced in Britain, they did not carry roofs, similar to older
horse carriages, and were not allowed to have one until the 1920s. Following the lifting of the prohibition, bus operators would use buses with roofs fitted due to climate conditions. However, some seaside towns retained a few open-top buses in their fleet for use on seasonal sightseeing services. Open-top buses are now primarily used as
tour buses for
sightseeing in cities and seaside towns, or around rural monuments or areas of special interest. These often include specialist information equipment, and colourful liveries illustrating the route. Open-top buses are used in some regions on regular
public transport transit bus services, in warm climates, or as seasonal services in temperate climates. Seasonal services are often in seaside towns, or along rural or coastal routes of particular scenic quality. Open-top buses are often used for victory parades for sport teams, and as temporary viewing platforms at events such as
The Derby. Vintage open-toppers can also be hired for events such as weddings. They may be used by notable people in a parade to ensure maximum visibility; this may be a security concern as with open-top cars; in 2009 an open-top bus carrying the
Dutch royal family was
attacked by an assailant. ==Types==