When his uncle became Pope Gregory XV (1621-1623), Ludovico Ludovisi was made a cardinal and, as befitted a cardinal nephew, began to purchase land for a villa and to acquire antiquities, buying up two celebrated collections that had been put together in the sixteenth century. Since his property, which lay in the valley between the Pincian and Quirinal Hills, was the site of the ancient Gardens of Sallust, he had the good fortune to uncover many buried antique masterpieces on his own land. Several of the statues were displayed in a wooded labyrinth (no. 5 on the plan) opposite the casino at the lower right. Just beyond this labyrinth in an uncultivated field, Falda has depicted an Egyptian obelisk lying on its side, another relic of the ancient gardens which was not re-erected until 1789. Today the cross-shaped casino at the left is the only remnant of the cardinal's gardens. It contains the magnificent ceiling fresco of Aurora that Cardinal Ludovisi commissioned from the Bolognese painter Guercino in 1621.