October 20 is the birthdate of English architect Sir Christopher Wren, who changed the public face of London after the Great Fire of 1666 by supervising the rebuilding of 52 churches, including his greatest single design, St. Paul's Cathedral (completed 1710). Other great Wren buildings include the south front of Hampton Court Palace and Trinity College library, Cambridge. In Wren's age, the profession of architect did not exist; it was a gentlemanly activity for a well-educated man, viewed as a branch of applied mathematics. An early Wren design was the Sheldonian Theatre at Oxford (1668, pictured), on the grounds of the Bodleian Library. It’s the site of music recitals, lectures and Oxford’s graduation ceremonies. Handel performed here, including the first performance of his third oratorio, Athalia (1733).