Tens of thousands of artefacts, some dating back to the Bronze Age, are to be brought out of storage in Kent.
Dover Castle is putting finds from the Richborough Roman Fort on display in a new public access area.
English Heritage has kept the collection in the old Royal Artillery Garrison Barracks since 1973, but has never had space to show it before.
Curators say they hope to rotate the display every six months so all of the items can be viewed.
Kevin Booth, curator of archaeology at the castle, said: "I wouldn't like to guess how many tens of thousands of artefacts are stored within this building - everything from the Bronze Age to the 1980s."
The items include collections of Roman coins, gilded monastic stonework and defunct radiation detection equipment.
The collection also includes furnishings from past Lord Wardens of Walmer - the official residence of the Lord Warden of the Cinque Ports is Walmer Castle, Kent.
Visitors will be able to see the artefacts in a special viewing room.