A walkway allowing visitors to see the hull of Henry VIII's flagship, the Mary Rose, is due to open in 2012.
The structure will be in place during the final phase of the wreck's conservation in Portsmouth Historic Dockyard.
The Tudor warship, which is being sprayed with a conserving solution inside a chamber, will begin a five-year drying process this year.
The walkway will give access to the chamber until the process is complete.
The chamber is due to be removed completely in 2016.
The ship sank while leading an attack on a French invasion fleet in 1545 and was raised from the sea bed in 1982.
The wreck has undergone 17 years of conservation treatment and is due to go on public display in 2012 when a dedicated museum will open in Portsmouth's Historic Dockyard.
The existing Mary Rose Museum will remain open during the construction of the new attraction.