The village of Purfleet falls within the parish of West Thurrock.
In 1765, in the reign of George III, Purfleet Garrison was built to service 5 powder magazines, arising from concern that powder stored at Woolwich presented a potential danger to London in the event of an explosion.

Much of the site has been demolished for a 1970s housing estate - the Garrison Estate. A few of the garrison buildings and parts of the inner security wall survive. The surviving buildings include the clock tower, which still contains a working clock.

The area is now one of seven conservation areas in Thurrock.

Another surviving building is the proofing house (known locally as the barrel store). In the proofing house, the quality of the gunpowder was tested before accepting a new delivery for storage in the magazines. This involved igniting a small quantity of gunpowder - a process known as "flashing".
The proofing house had become neglected and overgrown, but in 2003 it was restored by volunteers and with help from the Heritage Lottery and other sources.

The building is now used for local activities such as a toy library and a Saturday club for Dads and their children.

The gunpowder magazines were built of brick with thickly copper plated doors. The nails are copper and the roof space was filled with sand. There are no windows. All the buildings were designed to protect the surrounding area should an explosion occur. The magazines could each house over 10,000 barrels of gunpowder.
One of these magazines (No.5) survives and is a scheduled ancient monument. It now houses the Purfleet Heritage and Military Centre including a museum displaying household objects from the past as well as artifacts and photographs from all three services.