She's known as the mother of our modern underwater fleet. And, this week, divers have visited the wreak of one of Britain's very first Submarines.
Lying, upright in 30 metres of water - that's 100 feet - the Holland 5 was one of the first submarines accepted for service by the Royal Navy.
She sank 100 years ago and, to mark the centenary, the Nautical Archaeology Society dived to the site - to monitor her condition. Sarah Saunders went on an exclusive journey with them.
Click below to see the video
More top news
A number of teenagers, aged 13 to 15, from Portsmouth, have been treated in hospital, after taking tablets believed to be diazepam.
Thursday Evening's Pollen Forecast
Thursday night's weather for the east of the region