Fort Nelson, the military museum in Fareham, Hampshire, is to undergo a £3.5m revamp.

The fort – which was built in the 1860s as part of a chain of fortifications protecting the naval harbour of Portsmouth from the French – is home to the Royal Armouries collection of artillery, boasting more than 350 big guns and cannons.

The plans include a new visitor centre, Orienteur gallery and a classroom.

The Fort’s displays include the Great Turkish Bombard of 1464, Saddam Hussein’s infamous Supergun and the trebuchet from the movie Gladiator.