This sketch was made during Jones's second stay in Naples. It depicts the grotto at Posillipo, a tunnel cut by the ancient Romans to link Naples with Pozzuoli, further west along the coast. The tall, thin tunnel, depicted by numerous artists besides Jones, was a marvel of ancient engineering, and the tomb of the poet Virgil was to be found there, a site no cultivated tourist could miss. The tomb itself can be seen to the right of the main entrance of the tunnel.
The National Gallery, Trafalgar Square, London WC2N 5DN