Her Majesty’s Prison Portland was originally constructed in 1848 to house adult male convicts and to make use of their labour in the building of the harbour.
The site of the prison was originally chosen due to fears of a French invasion, the construction of a harbour over in Cherbourg and to maintain control over the English Channel. A prison was planned as early as 1846, a temporary public works establishment which would employ the men in quarrying stone and building the harbour.
Construction began in 1848, on the East side of the island, using plans drawn up by Surveyor-General of Prisons, Joshua Jebb. Work was well underway, undertaken by builder Peter Thompson, but by October it had surpassed initial costings and Thompson was bankrupt. The prison was completed in 1848 using a ragtag workforce drawn from all over the country and the first inmates arrived on the 24th of that same month.
Whilst inmates were being moved in, construction still continued on its buildings and even the Church of England Chapel wasn’t completed until late 1849. By 1853, the prison which had originally meant to house 800 inmates had almost doubled that. During the 1860’s Portland, like Woking and Chatham, began to house Fenians who had been convicted of serious offences, ranging from treason to sedition. In 1869 the temporary prison at Portland was made permanent. Once the dockyard was all but consturcted in 1872, the prisoners were then used to build parts of the town, namely St Peter’s Church.
As with many other prisons in the latter part of the 19th century, the numbers of convicts declined and discussion around shutting down Portland ensued. This however did not take place and building ramped up in the 1900s, turning previously wooden structures into stone.
Between 1921-83, Portland became a Borstal for young offenders. It still functions today as a Young Offenders Institution.