Designed by Norman Foster & Partners, the Great Court will open to the public at the end of 2000. At its centre will be the Round Reading Room, restored to its original 1857 state. It will house the new Paul Hamlyn reference library and multi-media research facilities to access the museum's archive.
The domed structure will have a new exterior of Portland stone, together with two elliptical floors on the outside providing exhibition space and catering and retail facilities. These will be accessed by two staircases and two lifts and there will also be a walkway to the upper levels of the museum's northern areas.
Beneath the courtyard, a new basement level will provide two auditoria and seminar rooms for the museum's Centre for Education.
The entire courtyard will be topped with a 6,000m2 steel and glass roof, supported by a concrete beam around the sides of the courtyard and a ring beam around the dome of the Reading Room. This ring beam will be independent of the Reading Room itself, supported by steel columns founded on the original pad foundations, underpinned with new jet grouted columns.
Work, being carried out by construction manager Mace, also includes rebuilding the south portico, demolished in late Victorian times to make way for a front hall extension. This will be to original design, although it will be slightly deeper to take in two lift shafts.