The Leyland National is an integrally-constructed British step-floor single-decker bus manufactured in large quantities between 1972 and 1985. It was developed as a joint project between two UK nationalised industries – the National Bus Company and British Leyland. Buses were constructed at a specially built factory at the Lillyhall Industrial Estate, Workington. Styling was carried out by the Italian vehicle stylist Giovanni Michelotti, previously commissioned by both Triumph (Herald, TR4, GT6, 2000/2500, 1300, Dolomite and Stag) and Scammell lorries (Routeman GRP cab). It was intended to replace all the rear-engined single-decker buses offered by British Leyland, including the AEC Swift, Bristol RE, single-deck Daimler Fleetline, Daimler Roadliner and Leyland Panther. Design The Leyland National was built with integral, modular construction and a rear engine. All components were designed for ease of construction and replacement. Until 1978, it was always built with a roof mounted pod at the rear, housing the heating equipment, which consequently blew warm air out at roof level. At first the pod was almost the length of a bay and appeared designed to give a Trans-Atlantic feel. In 1976 a new shorter version of the roof pod was introduced along with the battery being relocated to the front under the cab. The Leyland National was available in three lengths, the majority being and . It was easy to spot the longer ones as its main side windows were all the same length, on the shorter models the windows were shorter except for one in the middle (where the exit doors were on dual door variants) which was the same length as on the longer models. The third length was , specially produced for Australian operators due to stringent axle weight limits. This used the front section of the long version and the rear section of the short version. The prototype of this latter version was sold to a Scottish operator, Rennies of Dunfermline, and was fitted out to dual purpose specification for use on express services. The Leyland National was a simple design: all parts could be replaced. Some operators, like London Transport, bought dual door models, and then later configured some of them to single door. This was helped by the design of the body, the fact that parts were inter-changeable and that the bus was constructed using Avdelok rivets, specially designed for the National, instead of the more usual pop rivets screws or welding. The