Britain’s largest Napoleonic fortress, which was built to defend Chatham Dockyard centuries ago, is throwing open its doors on Saturday, August 9 and Sunday, August 10 for a free admission weekend and is putting on a number of activities.

Visitors can tour the fort’s haunted network of tunnels, enjoy live entertainment, historic re-enactments and an obstacle course.

Not all activities are free but visitors can also see the site’s newly revealed First World War gun, which has been unveiled to commemorate the 100th anniversary of the start of the Great War.

The summer fair runs from 10am until 4pm on both days.

Fort Amherst is in Dock Road, Chatham. For more details call 01634 84774 or go to www.fortamherst.com