The Church of the Madonna degli Angeli or Santa Maria degli Angeli (Basilica of St. Mary of the Angels), in the Piazza della Repubblica, Rome, was constructed inside the ruined frigidarium of the Roman baths of Diocletian in 1563-64 to designs by Michelangelo. At 90 metres long its great transcept emphasizes and exploits the vast scale of Roman constructions to dramatic effect despite the fact that Michelangelo raised the floor level from that of ancient Rome to that of the 16th century, truncating the original red granite columns in so doing. The distinctive semi-circular windows, each divided into three by two upright mullions, gave rise to the architectural term 'Diocletian window'. The thermae of Diocletian were the largest of the imiperial baths of Rome, constructed between 298 AD and 306 AD.

This dramatic view of the interior wtih its angled perspective and dramatic contrasts of light and shade, is from Piranesi's series of Vedute di Roma (Views of Rome).

On the right in this view, set into the floor, is is the meridian line (a sort of sundial) commissioned by Pope Clement XI from the astronomer Francesco Bianchini, which was finished in 1702.

Unknown. This print was in Soane's collection by 1796 when it is shown in J.M. Gandy's view of the No. 12 Breakfast Room 14/6/1 hanging on the west wall (centre of three framed prints shown there).