Limestone from the site
Work began in 1851, using limestone quarried on the site. The Comptroller General, Edmund Henderson, designed the Gatehouse, and Henry Wray oversaw the building’s completion after the Royal Engineers were recalled during the Crimean War.
The Main Cell Block
The design followed Pentonville Prison in Britain. Prisoners moved into the southern half of the Main Cell Block on 1 June 1855, and the northern wing was finished by the end of 1859.
Water from below
In the 1850s shafts were sunk beneath the prison to supply fresh water. The tunnels were closed in 1910 and opened to visitors in 2005.



