The mayor said his town had been put “on the map” as a filming destination after crews from the series Slow Horses were spotted in action.

Scenes for the fourth series of the Apple TV thriller, starring Gary Oldman, were filmed in Watford last year.

Production crews used locations at West Herts College, Watford Leisure Centre and Hempstead Road for the spy drama.

Mayor Peter Taylor said: “Hosting major productions like the Apple TV series Slow Horses not only puts Watford on the map as a prime destination for future film and television projects, but also brings economic benefits to our town.”

Earlier this year, the Hertfordshire Film Office launched a website to promote the area to potential filmmakers.

It was created by the Hertfordshire Local Enterprise Partnership, with funding from Hertfordshire Growth Board and district councils.

The area is a popular destination for filmmakers as it is home to both Elstree Studios – owned by Hertsmere Borough Council – and the Warner Bros Studios at Leavesden.

Dacorum Borough Council said the town of Hemel Hempstead had also become the “UK’s answer to Hollywood”.

Mr Taylor added: “We’ve seen first hand how such productions boost local businesses and create job opportunities.

“To help promote what the county and Watford has to offer, the Hertfordshire Film Office offers a seamless, one-stop support service for productions filming in the county, including location matching, highway permits, traffic management, and access to local crews.

“As Hertfordshire becomes a key hub in the UK’s rapidly growing Creative and Screen Industry, we want to maximize the sector’s potential and position the town and county as a premier filming destination.”

Deputy mayor Aga Dychton said Watford was an attractive location for film and television makers due to the diversity of buildings and closeness to London.

She told BBC Three Counties Radio that another production had used Market Street in recent months.

Ms Dychton explained: “It’s quite interesting to see a small town with very characteristic buildings get opportunities where in the past nobody would look at it when there’s big cities.”