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As Finberg correctly identified, this sketch depicts the Piazza Colonna, a square in the heart of Rome, so called because of its main landmark, the Column of Marcus Aurelius. The details of the drawing reveal that Turner must have been standing in front of the Palazzo Chigi and looking across to the south side of the piazza, dominated on the left by the Palazzo Ferraioli and on the right by the Church of San Bartolomeo dei Bergamschi. Rising from the left-hand foreground is the column itself. Erected in AD 180 to commemorate the military victories of Emperor Marcus Aurelius the monument is decorated with marble reliefs and is topped by a bronze statue of St Paul. Related studies can be found on folios 82, 87, 89, 90 and the inside back cover (D16624, D16632, D16635, D16637 and D40957).