Brave souls can now have a sleepover inside Britain's 'most haunted' prison

Brave ghost hunters can spend the night at Britain's 'most haunted' prison - curled up inside a cell that once held dangerous inmates.

Shepton Mallet prison still has the unmarked graves of executed prisoners and was once home to child killers, rapists and notorious gang members.

The Kray twins - Ronnie and Reggie - were transferred to the prison in Somerset from the Tower of London after absconding from the military in 1952.

The former jail, which closed six years ago, is now open to tours and fans of the supernatural are being given a chance to stay overnight to hunt ghosts while getting a taste of prison life, Bristol Live reports.

Staying overnight at Shepton Mallett prison promises to be a terrifying experience (Devon Live)

When it closed in 2013 HMP Shepton Mallett was the oldest operating prison in the UK, with a capacity for just under 200 high-risk prisoners at its peak.

But now it is said to be haunted, with one visitor claiming to have heard doors slamming shut and footsteps with no-one else around.

Events company Bump in the Night is hosting a series of overnight tours and sleepovers which could be a thrilling but terrifying experience.

Visitors can sleep inside a cell that once held dangerous prisoners (Devon Live)

The tours first launched two years ago and they will resume in October for a limited time in the run-up to Halloween.

Brave visitors will be given snacks and ghost hunting equipment as they roam through the prison at night.

People can stay until 2am or 6.30am if they want to sleep over.

Convicted killers were executed at the prison in Somerset (Bath Chronicle)

A Bump in the Night employee said: "Since I started working for Bump In The Night I've been on quite a few night-time tours of the prison and they really are terrifying.

"I wasn't convinced it would be that scary before my first one but that has definitely changed now.

"I've seen and heard all sorts including shadows when nobody is around, doors slamming shut and footsteps only to see nobody there.

Men, women and children were held in hideous conditions (Bath Chronicle)

"When we were in the prison once my colleague leapt up from his seat and ran across the room.

"I asked what happened and he said he heard a loud growling sound in his ear, but we were the only two people in there."

The prison first opened in 1625 and under went a number of expansions and changes over the centuries.

Today, it is a historic site that also offers daylight tours.

The prison building is Grade II-listed, while the walls are Grade III-listed.