BEHIND the walls, through the alleyways and beneath the streets of Bradford city centre lies a dark criminal history.

In Sunbridgewells, the subterranean bar and retail complex, two ‘skeletons’ languish behind bars - once the site of holding cells beneath an 18th century courthouse. Further down Ivegate, a backstreet area held prisoners prior to transportation to Australia.

And beneath the civic offices of City Hall lies a labyrinth of Victorian police cells where prisoners were locked up for over a century. Among them were murderers, German airmen whose plane crashed on a cottage in Idle in the Second World War, and illusionist Houdini, who escaped from a cell in a stunt while in town for a show at St George’s Hall.

These days the cells are used for filming - in TV’s Peaky Blinders and The ABC Murders and soon-to-be-released film Official Secrets, starring Keira Knightley - and two days a week they are open to visitors at Bradford Police Museum.

The museum is located on the site of Bradford’s main police station, court and chief constable’s office, based at City Hall from 1873-1974.

In 1974, when the Tyrrells police HQ opened, the cells were taken over by the prison service and used until 1990, while the courtroom was a crown court. Graffiti covering cell walls from that period is still visible. More recently some cells were painted a murky green by the Peaky Blinders crew.

Visitors are taken to the cells - and up into the Victorian courtroom, where dramatic scenes in Emmerdale and Coronation Street are often filmed - and the museum also holds occasional ghost tours which are so popular monthly tours are planned for next year. Halloween tours on October 31 and November 1 will feature candlelit tales of ghosts said to haunt the cells, including prolific burglar of many guises ‘Chains Charlie’ and a young girl, one of many children imprisoned there. There are also tales of police figures such as James Berry, a constable who became a hangman in the 1880s and hanged 130 people over 10 years.

“The ghost tours are hugely popular. Some visitors say they’ve felt someone touching them, or walking past,” says museum director Martin Baines, a retired police inspector who locked up many prisoners in the cells.

Following the success of a walking tour through Bradford’s criminal past, the museum is also planning more walks taking in murder scenes and sites of old police stations and courthouses. Other plans include a re-creation of a doctor’s surgery, with 19th century medical items.

The Police Museum was set up in 2014 by Martin and his daughter, a historian. Run by Under the Clock charitable trust and staffed by retired police officers, it’s a fascinating journey through Bradford’s history of policing, crime and punishment. “We get visitors from around the world; visitor numbers are up each year,” says Martin.

Artefacts displayed in the former parade room include painted truncheons, handcuffs and uniforms. In an office set up as it looked in the early 20th century there’s old radio equipment, a detective’s coat and a 1930s restraining chair used for violent prisoners, known as ‘Sparky’ because it resembles an electric chair.

The museum highlights Bradford’s pioneering police work. The city had the first conviction by fingerprint evidence outside London, in 1905; the first colour photograph of a crime scene, in the 1930s; the first short wave radio transmission to a police vehicle, from Northowram to Bradford, in 1936; and the first tape recording of a murder confession used in court, in 1964. When a woman was fatally stabbed at her home in Tennyson Place, her husband and another relative were interviewed in the cells and confessed to her murder, and a tape recording of the confession was used in court. “It set a legal precedent,” says Martin. A copy of the tape recording is on display.

The museum also has a fleet of historic police vehicles, donated by West Yorkshire Police and stored at Keighley Bus Museum. The vehicles, displayed occasionally at classic car shows in Centenary Square, include a Mini Metro police car and a black Ford Consul with blue light.

“We’re looking for volunteers to look after the vehicle collection, and to work at the museum, as guides and front-of-house. We train them, they don’t need a police background,” says Martin, who joined the force in 1974 and was involved with high profile investigations including the Ripper case. “Policing is social history. It has changed so much over the years - when I started there was one computer, used for checking car number plates - and this museum traces and preserves the history of policing and the men and women who worked here.

“We get donations all the time, from retired bobbies and people whose relatives were in the force. We’d like to develop an oral history, to preserve the city’s story of policing.”

* Bradford Police Museum is open Fridays 11am-3pm and Saturdays 12-4pm. It will close in November for a winter break until next March. Visit bradfordpolicemuseum.com or call (01274) 510245.