This style of wine has matured in the bottle and once opened, is meant to be served as one would an aged red wine, that is decanted and enjoyed across a couple of days. These wines are not a Tawny or like a barrel aged Tawny and are not designed to be placed in a barrel.
It is also recommended to use an Ah-So Wine Opener to remove the cork from an aged vintage bottle of wine as opposed to a conventional cork screw which can fracture the old corks in the opening process.