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The subject at the bottom of the page is the sanctuary of Santa Maria di Galloro, a church by Bernini which stands just outside of Ariccia on the Via Appia Nuova towards Genzano, see also folios 87 and 88 (D15461 and D15463; Turner Bequest CLXXXII 86 and CLXXXII 87). The top and middle sketch meanwhile both depict a distant view of Ariccia, recognisable from the profiles of the Church of Santa Maria dell’Assunzione and the Palazzo Chigi. The orientation of the dome and the twin bell-towers, also designed by Bernini, demonstrates that Turner’s viewpoint must have been south-east of the town. Coupled with his inscription ‘These 3 are the same’, this suggests that he probably drew all of the three sketches standing in the same spot i.e. near Santa Maria di Galloro, but looking in different directions.
For a general discussion of Ariccia see folio 83 verso (D15455; Turner Bequest CLXXXII 82a).