Diagram at left shows one final lifting of the 17th century Vasa . Heavy nine-inch wires are drawn under the old oak hull deep into the mud covering the bottom of the Stockholm waterfront. Centre - the two pontoons are drained and the ship rises three metres . New wires are put under the hull and it is again lowered to the bottom. Right - during the lifting of the Vasa whe will be towed gradually into less deep water . All the time , divers are working to repair all small leakages. When the upper deck reaches the surface , the draining starts. 17 April 1961