Although its Tolpits Lane factory closed in 1988 and was demolished to make way for housing, a business estate and industrial park, Scammell remains arguably the best known British manufacturer of trucks, particularly of more specialist vehicles.

The Scammell business was originally developed in Spitalfields in London, but the firm moved to Watford and on May 1, 1922, Scammell Lorries Ltd was incorporated.

The Tolpits Lane factory and offices in their final form in 1983

Exactly one hundred years later this historic anniversary will be marked by a celebration of all things Scammell at King George V Playing Fields on Sunday.

The event is being organised by the Scammell Register, the worldwide enthusiasts club for the marque, and will take place from 10am to 4pm.

The central attraction will be a gathering of Scammell lorries and Parry Davis, from the Register, is hopeful that between 30 and 50 vehicles will be in attendance.

These are likely to include the firm’s famous three-wheeled vehicle, the Scarab, and military lorries; Scammell was a major supplier of heavy equipment to the British armed forces until the Watford factory closed.

The Scammell Scarab

Following the gathering, the vehicles will head out on a celebratory drive that will follow the route the company used for its road tests.

After leaving the playing fields, the vehicles are due to take the A412 to Denham, the A40 to the Polish War Memorial, before turning north back towards the A404 and returning to King George V.

However, Parry explained that in order to avoid making a tight right-hand turn into the playing fields, which some of the vehicles would not be able to negotiate, they are set to continue along Tolpits Lane and Whippendell Road to use a roundabout before returning to their starting point.

A locomotive is transported by a Scammell vehicle in 1948

Parry, who thanked Watford Council, Watford Museum and Watford & District Classic Vehicle Trust for their help and support in staging the event, believes there are between 150 and 250 Scammell vehicles that are still roadworthy, the oldest of which is more than 90 years old.

He said: “The oldest one we know of is a 1928 chain drive that is back on the roads with its original registration number.

"It was just luck. We managed to find some documentation, the DVLA accepted it and it’s back on the road with its original registration. It has however been converted from solid tyres to pneumatics.”

Admission to Sunday’s gathering at King George V Playing Fields is free.