From 1659-1660, Alexander VII undertook a project of constructing a new ship-building arsenal at Civitavecchia, led by the famed artist and architect Gian Lorenzo Bernini. This medal shows the initial layout for the proposed six bays of the arsenal, present as a row of six parallel openings at the rear of the harbor, directly to the left of the fort which is present on the right. For the final design, the bays were split into pairs which were set at an angle of 30° to one another. A smaller, struck medal was later made in 1660 with this final design. The identification of the location as the Port of Centumcellae refers to the original name for the harbor, which had been constructed by the emperor Trajan.