Mention the word asylum in connection with people who have a mental illness and it conjures up all sorts of images.

You can be forgiven for considering this a rather murky part of our history, as these were institutions where patients were often shut away, some for many years at a time, and subjected to unknown horrors in the name of "treatment".

It was far removed from the original meaning of the word asylum, as a sanctuary.

Therefore, it is no surprise that such outdated medical practices and the hospitals that used to house the patients no longer exist.

Many of the terms that once accompanied them, such as "lunatic" or "imbecile" are also now deemed inappropriate.

But they were accepted in the 1800s, when provision of asylums in every county became law.

Here we look at those set up in Kent and what has happened to them since.

Darenth Park

The Darenth Asylum and Schools was built for "imbecile children" at the instruction of the Metropolitan Asylums Board.

It was constructed by A&C Harston and cost £88,750, according to workhouses.org.uk, a website created by Peter Higginbotham, who regularly contributes to hit BBC shows Who Do You Think You Are? and Heir Hunters.

It opened in 1878, initially for 560 youngsters aged five to 16.

The daily routine was a mix of classroom lessons and learning practical skills.

Two years after it opened, the school was expanded and a building that could accommodate 1,000 patients was added.

With growing demand for places for adults, more buildings went up in the late 1880s, 10 in total, five for men and five for women.

Darenth went on to become a training centre, or colony as they were known, with patients taught skills that helped support the board's other institutions, such as making clothes and bedding. It even had an asylum farm.

Following its closure in 1988, it was demolished and the site was cleared.

The land was subsequently used for Darent Valley Hospital.

Oakwood Hospital

Originally known as the Kent County Lunatic Asylum, it opened in 1833 and could house up to 1,577 patients at its Barming Heath site, near Maidstone.

The building was designed by John Whichcord, who was also responsible for drawing up the plans for Maidstone Prison.

It was the principal location for those considered in need of institutionalising in Kent, and took in people from all over the county, as well as from London.

Over the years, it expanded and among the additions was a third patient area, known as Hermitage Block.

Demand for beds became acute and at one stage it accommodated 2,000 patients, leading to the need for alternative provision to be found elsewhere.

In 1957, the hospital was the scene of a tragedy when a tower collapsed following a fire, killing seven people and injuring many more.

When the policy of keeping mentally-ill people in institutions for many years was ditched towards the end of the 1900s, and services were transferred to Maidstone Hospital, Oakwood was closed.

The buildings that remained, all Grade II-listed, have been converted into apartments.

The complex is known as St Andrew's Park, which was the name of the hospital's original main building.

St Augustine's, Chartham, near Canterbury

Perhaps the most notorious of Kent's asylums, it was opened in 1875 after it became apparent that the existing institution at Barming was not big enough.

It was originally known as the East Kent County Asylum and had room for 1,205 patients.

Its large site, on Chartham Downs, meant that it could be self-contained, and it had a farm, baker, butcher, chapel and even a cricket team. It was also home to Beech House Hospital School, which was in use up to the 1990s.

In 1920, it was re-branded as Kent County Mental Hospital, becoming St Augustine's when it was taken on by the NHS in 1948.

It was in the 1970s when it achieved national notoriety, after university researcher Brian Ankers, who was employed there as a nursing assistant, raised concerns about abuse and neglect of patients.

Initially, his complaints were rejected, so he and another nurse put together a list of 70 occasions when patients were abused, neglected and degraded.

Their actions forced an inquiry and most of the complaints were upheld. The management was condemned, particularly for the way it used electroconvulsive therapy - passing electrical currents through the brain.

In the proceeding years it was, however, deemed fit enough for royal visitors, with both Princess Anne and Princess Diana welcomed there.

The hospital shut in 1993 and most of its buildings, although not the chapel, were demolished. In the late 1990s, work began on redeveloping the area as a housing estate, which is still known as St Augustine's.

St Martin's Hospital, Canterbury

The need for an asylum in Canterbury came about due to a local government reshuffle in 1889, when the city became a County Borough, independent of the rest of Kent.

Under the County Asylums Act, it was required to open one and plans for a Canterbury Borough Asylum to be built in Littlebourne Road were drawn up.

Before then, the city's patients had been despatched to other asylums, some many miles away.

It opened in 1902 in what had been a manor house, called Stone House, and its capacity of about 250 beds made it one of the smallest institutions of its kind in the country.

As with many things in Victorian England, those that could afford it were offered better accommodation, and wealthy private patients were housed in a separate house in the grounds.

After the First World War, it became known as Canterbury City Mental Hospital, and was renamed St Martin's, after the church nearby, following the Second World War.

More buildings were added over the years, although the manor house is among the structures to have been demolished.

Much of its day-to-day administration was taken over by St Augustine's, although when that closed, more buildings were added to St Martin's.

Care for mental health patients continues to be provided there. A £10million extension was officially opened in 2012.

West Malling Lunatic Asylum, High Street, West Malling

Aside from state-sponsored institutions, a number of privately-run establishments had already been in existence for some time.

Among the more notable in Kent was one founded in the 1760s by William Perfect, a doctor who had a particular interest in treating people deemed to be insane.

His practice, also known as Dr Perfect's asylum, was in West Malling High Street and it was also his home.

Patients would be invited to stay with him and, according to research by The Malling Society, he advertised his services in newspapers.

It is understood he was nicknamed the 'Mad Doctor', something author Shirley Burgoyne Black seized upon for her book, An 18th Century Mad-Doctor: William Perfect of West Malling.

She wrote that he became "a successful practitioner at a time when few men considered it possible to relieve the insane, nervous and hysterical patients".

Socially, Perfect was well-known in freemason circles and became provincial grandmaster of Kent.

He died in 1809 but the asylum continued to be run by his son, George. When it failed financially, it changed hands and was moved to Malling Place but ceased taking patients in the late 1900s.

A blue plaque acts as a reminder of the Grade II-listed high street building's former resident.

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