A major facelift is planned for the Royal Armouries Museum at Fort Nelson in Fareham, and it will be unveiled to the public on Monday, October 20.
The massive scheme involves upgrading facilities at the museum on Portsdown Hill – home to one of the most important international collections of historic cannon in the world.
The Fort Nelson improvements are necessary as visitor numbers grew from 39,000 to 90,000 between 2000 and 2005.
Proposed improvements include a new visitor centre, a major new gallery structure to house the largest, most iconic objects in the collection and a state-of-the-art education centre.
The fort is not a listed building but is registered as an ancient monument and so any development on the site must be in keeping with existing structures. Royal Armouries staff have had to work closely with English Heritage to make sure the designs were acceptable.
A £2m lottery grant is meeting most of the cost with the rest coming from Royal Armouries.
The plans will go on show at the fort between 5pm and 7pm on Monday. The project development team will be on hand to answer questions.
Residents of the area around Fort Nelson such as Southwick, Portchester, Boarhunt and Wickham are particularly invited to attend but all are welcome.
Sean Mannie, head of Royal Armouries South, said: 'Public backing for this project is very important to us and we hope to canvas the views of as many people as possible.'
Mr Mannie added: 'This success has placed great strain on the historic monument and its facilities which were not originally designed for the volume of visitors now coming in.
'For Fort Nelson to have a long-term future, it is vital that it reacts and develops to meet the needs of even more visitors and the long-term care of the collection. Now the Royal Armouries, with the support of Hampshire County Council, who own the fort site, have created an exciting development plan that will enhance the whole site, providing better facilities.'

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