The Vasa, Stockholm's famous warship, survived more than 300 years under water, but its life in one of Scandinavia's most popular museums has proved more complicated. A large metal structure is being installed as part of a colossal four-year project to save it from deteriorating. The ship, one of the Swedish capital's main tourist attractions, sank on its maiden voyage in 1628 and remained at the bottom of the sea until it was salvaged in 1961. By 2028 -- if all goes well -- the hull will be supported both externally and internally, and the current 17 external struts will be replaced by 27 steel cradles with fixtures under the keel. IMAGES AND SOUNDBITES ARRANGED IN SEQUENCES