The amazing glazed roof and interior in the Great Court of the British Museum in London was once a open courtyard. In the mid-1800's the circular Reading Room was built at its centre. But after an architectural competition in the late 1990's, the Queen Elizabeth II Great Court, designed by Foster and Partners,turned the courtyard into the largest covered public square in Europe. The two-acre space was enclosed by this spectacular glass roof with the Reading Room at its centre.