The Roman antiquities, t. 4, Plate XXIV. Elevation of the bridge and its foundations Cestius. 

This etching by Giovanni Battista Piranesi is a detailed cross-section of the foundations of the Ponte Cestius, a bridge in Rome, Italy. Piranesi, known for his dramatic depictions of ancient Roman ruins, created this as part of his series "Roman Antiquities," highlighting the architectural ingenuity and scale of Roman engineering. The intricate detail, with labeled sections showing the different layers of the bridge's construction, exemplifies the meticulous approach of Piranesi's work and his fascination with Roman history. The use of precise measurements adds to the scientific nature of this engraving, offering a glimpse into the architectural knowledge of the time.