The transformation of buildings on Swallow Street in Bath into a Clore Learning Centre for the Roman Baths and a World Heritage Centre for the city has begun.
The conversion is being carried out by Beard Construction, who are now on site.
The National Lottery-funded project will improve learning and engagement at the Roman Baths.
The project team will work with local community groups and schools from across the region on events, activities and sessions for school groups.
Workshop leaders will lead new learning opportunities to investigate the Romans and the science of archaeology, in an exciting Investigation Zone set amongst the Roman remains of the archaeological site.
The World Heritage Centre will contain imaginative displays that will show people why the city of Bath is a World Heritage Site and inspire them to go out and explore the city. It will be free to visit and welcome everyone.
The project, supported by £3.4m from The National Lottery Heritage Fund, will also open up new areas of the Roman Baths to visitors, including a Roman laconicum (similar to a sauna) and a possible Roman exercise yard.
The new facilities are due to open in 2020.
Councillor Paul Crossley, cabinet member for Community Services at Bath & North East Somerset Council, said: “We are delighted to see the creation of the Learning Centre and World Heritage Centre beginning.
“The new spaces will be accompanied by exciting community events, activities and learning opportunities – from wellbeing courses for local community groups, to a digging pit where school children can unearth replica Roman objects.
“In addition, we hope to attract visitors from around the world to see parts of the Roman Baths that will be revealed to the public for the very first time.”
The work will be undertaken by Beard Construction, who have a long history of carrying out projects involving historic sites, and of protecting heritage buildings throughout the south of England.
Mike Hedges, Beard Bristol director, said: “We are delighted to be back at the Roman Baths again, where we undertook work on the Temple Precinct back in 2013/2014, installing a walkway to enable easier visitor access to this historically important site.
“This new project will provide visitors with a hands-on learning experience set among Roman remains and help showcase Bath’s rich and fascinating heritage.”