Archaeology
Vasa posed an unprecedented challenge for archaeologists. Never before had a four-story structure with most of its original contents largely undisturbed been available for excavation. The conditions under which the team had to work added to the difficulties. The ship had to be kept wet in order that it not dry out and crack before it could be properly conserved. Digging had to be performed under a constant drizzle of water and in a sludge-covered mud that could be more than one meter (approximately three feet) deep. In order to establish find locations, the hull was divided into several sections demarcated by the many structural beams, the decking and by a line drawn along the center of the ship from stern to bow. For the most part, the decks were excavated individually, though at times work progressed on more than one deck level simultaneously.
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