The Royal Naval Museum, Portsmouth

The museum is devoted to the ships of the Royal Navy and the men and women who served in them. A special exhibition covers the Battle of Trafalgar. Many paintings and contemporary ship models of that time are shown.
The galleries devoted to the 20th century Navy focus on the changing face of the service from the launch of the Dreadnought to the Falklands War.

There is more information on the museum in the homepage of Portsmouth Historic Dockyard and the website of the Royal Naval Museum. 

I liked very much the fine collection of figure heads in the museum. I took some pictures of them, being 500 kB in total. If you click on a photo you will get that photo in high resolution. (If you use Microsoft Internet Explorer or Firefox, press F11 to minimize navigation bars and have a larger screen with the photos.)