Belmarsh Prison opened almost 25 years ago and was the first adult prison to be built in London since Wormwood Scrubs in 1874. The bulk of the prison is on a large site surrounded by a perimeter wall about 1 mile long.
The prison has 4 house blocks, each 3 storey and each with 3 spurs. Each spur contains 42 single and double cells.
- House block 1 – 174 older prisoners, life sentence and mixed population.
- House block 2 – 174 on short sentences, remands and mixed population.
- House block 3 – 174 on first night centre/induction and remand prisoners.
- House block 4 – 171 on vulnerable prisoners spur and mixed population.
- High secure unit (HSU) – a self-contained unit holding up to 47 prisoners who require a high level of security (including a small discrete segregation unit for HSU prisoners only).
- Segregation unit – holding up to 16 prisoners serving periods of punishment or needing to be separated from others. It also contains two designated prison rule 46 cells used for the temporary management of close supervision centre (CSC) system.
- Health care inpatients – a 33-bed inpatient facility