When did Hagia Sophia become a museum?
Hagia Sophia
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The vast interior has a complex structure. The nave is covered by a central dome which at its maximum is 55.6m (182ft 5in) from floor level and rests on an arcade of 40 arched windows. Repairs to its structure have left the dome somewhat elliptical, with the diameter varying between 31.24 and 30.86m (102ft 6in and 101ft 3in).