pyramids were modelled on the much less steeply pointed Egyptian pyramids exemplified by the famous pyramids of Giza. However, the relatively shallow Giza-type pyramids were not exclusively used by the Egyptians; steeper pyramids of the Nubian type were favored by the Ptolemaic dynasty of Egypt that had been brought to an end in the Roman conquest of 30 BC. The pyramid was, in any case, built during a period when Rome was going through a fad for all things Egyptian. The fusion of Roman and Egyptian styles is further highlighted by the fact that the exterior is distinctly "egyptianizing", while the interior displays classic Roman fresco paintings and a barrel vaulted ceiling. The Circus Maximus was adorned by Augustus with an Egyptian obelisk, and pyramids were built elsewhere in the Roman Empire around this time. During the construction of the Aurelian Walls between 271 and 275, the pyramid was incorporated into the walls to form a triangular bastion. It was one of many structures in the city to be reused to form part of the new walls, probably to reduce the cost and enable the structure to be built more quickly. It still forms part of a well-preserved stretch of the walls, a short distance from the Porta San Paolo. The origins of the pyramid were forgotten during the Middle Ages. The inhabitants of Rome came to believe that it was the tomb of Remus (Meta Remi) and that its counterpart near the Vatican was the tomb of Romulus, a belief recorded by Petrarch. Its true provenance was clarified by Pope Alexander VII's excavations in the 1660s, which cleared the vegetation that had overgrown the pyramid, uncovered the inscriptions on its faces, tunnelled into the tomb's burial chamber and found the bases of two bronze statues that had stood alongside the pyramid. The pyramid was an essential sight for many who undertook the Grand Tour in the 18th and 19th centuries. It was much admired by architects, becoming the primary model for pyramids built in the West during this period. Percy Bysshe Shelley described it as "one keen pyramid with wedge sublime" in Adonaïs, his 1821 elegy for John Keats. In turn the English novelist and poet Thomas Hardy saw the pyramid during a visit to the nearby Protestant Cemetery in 1887 and was inspired to write a poem, Rome: At the Pyramid of Cestius near the Graves of Shelley