As part of a BBC News website investigation into the state of British prisons, we chart the history of our jails.
1166 - HENRY II BUILDS JAILS
These include Newgate Prison in London. Henry also establishes courts in England.
The first legal textbook is produced and becomes a precursor to Common Law.
The modern jury is set up with 12 free men to adjudicate on land disputes.
1215 - MAGNA CARTA SIGNED BY KING JOHN
Marking the beginning of English judicial rights, it states that no man can be imprisoned without trial by his peers.
Article 39 - "No free man shall be arrested, or imprisoned, or deprived of his property, or outlawed, or exiled, or in any way destroyed, nor shall we go against him or send against him, unless by legal judgement of his peers, or by the law of the land."
People who refuse to be tried by jury are put in prison.
Conditions are primitive. Prisoners sleep on bare earth and are given bread and water every other day.
Jailers charge for everything - food, blankets, fuel - even to have manacles removed.
Houses of Correction are established to control a growing vagrancy problem.
The "idle poor" are locked up and punished for their "laziness". It is up to magistrates to decide if they can be released.
Inmate numbers soar. There is a growing reluctance by juries to sentence people to the gallows for petty crime. The alternative is to offer criminals a pardon if they join the Army or Navy.
England's prisons are over-crowded. The Industrial Revolution at the end of the century leads to the displacement of many people and an increase in petty crime.
Numbers are swelled by debtors and in the later part of the century prisoners of war from the conflicts with Napoleonic France.
Derelict ships or "hulks" in the Thames and southern ports are used as floating prisons.
1786-1791 - TRANSPORTATION TO AUSTRALIA
In response to the severe pressure on the prison system - and as an apparently more humane punishment than execution - transportation to North America is developed.
Around 50,000 criminals are settled there but the American War of Independence ends that option. Australia is the alternative.
The first fleet with 775 prisoners goes in 1786, followed by three large fleets between 1787 and 1791, which form the basis of the population of the country.
1777 - JOHN HOWARD PUBLISHES JAIL REFORM BOOK
As High Sheriff of Bedfordshire, Howard studies prison conditions for 17 years.
He proposes they should be healthy and disease-free, and that jailers should not be allowed to charge prisoners.
The book, called State of the Prisons in England and Wales, is highly influential but not widely put into practice until the 19th Century.
The Howard League for Penal Reform - still influential today - is named after him.
1791 - PHILOSOPHER JEREMY BENTHAM DESIGNS HIS PANOPTICON
Bentham sees it as the ideal prison. The key concept is to allow guards to observe the prisoners without them knowing.
It is never built as intended but is the model for, among others, the Pentonville and Millbank prisons.
1815 - JAILERS NOT ALLOWED TO CHARGE INMATES
The state now pays jailers, and magistrates are given responsibility for inspecting prisons.
In 1835 prison inspectors are introduced and by 1877 all prison staff are salaried and appointed on merit.
1817 - ELIZABETH FRY CAMPAIGNS FOR REFORM
A Quaker, she is appalled at prison conditions and over-crowding.
She founds a prison school for children held with their mothers and sets up Association for the Improvement of the Female Prisoners in Newgate.
She and her brother Joseph John Gurney persuade Home Secretary Sir Robert Peel to introduce prison reforms.
In 2002, her image is depicted on the Bank of England £5 note.
1878 - PRISONS ACT
This leads to closure of the worst prisons and all prisons are brought under the control of a national system run by the Prison Commission. It has to submit annual reports on prisons to Parliament.
The act also sees the adoption of John Howard's reforms and a shift in emphasis from prisons being a place of punishment to reform.
And two new ideas are introduced - "decarceration", which replaced sentences with supervision in the community, and "therapeutic incarceration", which reduces the punishment element in imprisonment.
1922 - SEPARATE CONFINEMENT ABOLISHED
Regimes of keeping prisoners in silence or alone had been criticised for creating high instances of insanity.
Four hundred volunteer teachers start working in prisons. But wardens - which in 1919 are renamed prison officers - are not keeping pace with reform so in 1935 the first staff training course is launched at Wakefield Prison.
World War II leads to an increase in the number of female officers.
1948 - CRIMINAL JUSTICE ACT
This creates a model for modern day prisons.
It recommends longer periods of imprisonment for training and rehabilitation and efforts are made to involve staff in the reform of prisoners.