The galleries will be used to display some of the site's archaeological items
An education centre and new galleries are to be built at a Roman fort running near the central section of Hadrian's Wall In Northumberland.
The Heritage Lottery Fund has awarded £4m for the scheme at the Vindolanda Fort and Museum site.
The galleries will be used to display some of the site's archaeological items for the first time.
Vindolanda Trust director Patricia Birley described the grant as an "immense boost".
She said: "This exciting project will vastly improve the resources and opportunities that our Vindolanda and Roman Army Museum sites are able to offer to our visitors, education groups and archaeological volunteers.
"It and will facilitate a return to Vindolanda of some of our famous writing tablets by way of a loan from the British Museum."