Archaeologists have unearthed hundreds of skeletons at a 16th Century burial ground in the heart of the city that once served London's most notorious psychiatric hospital, the original ‘Bedlam’.

The bones are expected to yield valuable information about mortality, diet and disease in the period.

They were discovered while experts surveyed a site that is destined to become a new ticket hall for the capital's Crossrail project at Liverpool Street Station.

Opened in 1247, the Bethlehem Royal Hospital began admitting the mentally ill in the 14th Century, eventually becoming known by its middle-English abbreviation Bedlam.

The name became synonymous with disorder and confusion and struck fear into the heart of Londoners. The horror of its conditions, were immortalised in a painting by William Hogarth in 1735.

The picture is the last in a series of eight depicting ‘A Rake's Progress’ - a moral tale of a spendthrift young heir who squanders his money on drink, prostitutes and gambling.

He is eventually thrown into the old Fleet Prison close to the River Thames and ends up in Bedlam.

The burial ground was used from 1569 to the mid 19th century for Bedlam's patients and local residents when other cemeteries became overcrowded.

Jay Carver, lead archaeologist for the huge Crossrail project which bisects the old city of London, said the well-preserved bodies were discovered after trial pits were dug.

‘We've identified at least 100 individual burials within our small trial pit and, extrapolating that, it is very likely there will be several hundred if not a thousand plus..,’ he told Reuters.

The skeletons, many found just 1.5 metres (5 ft) below street level, will be studied by experts at the museum of London, before being reburied.

‘It's interesting on the archaeological side because the 16th century is a time of immense poverty really in the outer areas of the city of London. Sites of this type haven't always been fully investigated,’ Carver said.

The team also uncovered pottery fragments, clay pipes, animal bone artefacts, including knife handles, and, as yet, unidentified implements in association with the burials.

Towards the end of the 17th Century, the hospital moved to Moorfields in north London, now the site of Finsbury Circus.

Despite the new buildings with their well-kept gardens, the treatment of the mentally ill did not greatly improve - in the 18th Century, the public could visit Bedlam to stare at the patients for the price of one penny.

That practice died out long ago but the institution, now called the Bethlem Royal Hospital, still exists, in Bromley, southeast of London.