The ship which carried Norfolk's Lord Nelson to triumph in the Battle of Trafalgar is rotting away.
A new survey of HMS Victory, which is in dry dock in Portsmouth, showed extensive damage to her keel.
Experts say restoring her will be a very long and expensive process if her heritage is to be preserved.
Security has been stepped up at Norwich Castle Museum after a number of items celebrating the life of the Norfolk naval hero Lord Nelson were taken.
The news comes at a time the museum's displaying an Italian masterpiece worth £100 million.
Police are reviewing CCTV and the National Security Adviser for the Arts Council is reviewing the museum's security arrangements.
The theft was noticed by an off-duty police officer who saw the cabinet which housed the objects had been tampered with.