THE ever-impressive Redoubt Fort will open to visitors free of charge on Bank Holiday Monday.

The Napoleonic fortress is steeped in history and was built to protect Harwich and its harbour against French invasion.

Harwich Society members have spent the last 45 years breathing life into the structure, making it the largest historic monument in Britain being restored by a volunteer group.

Among a host of attractions on offer, visitors can see some of the original guns on display, have a stroll around the restored chambers and enjoy stunning views across historic Harwich.

Event organiser Dan Beck said: “The Redoubt Fort open day is a firm favourite with local residents and visitors alike and the Harwich Society volunteers very much look forward to showing off Old Harwich’s hidden gem.

“The Redoubt itself is the star of the show and it never fails to impress.”

The open day take place from 11am-4pm and will be free of charge, although donations to the society are welcome.