their ship. It immediately curled itself around the ship's mast and this was deemed as a good sign by them. Upon their return up the Tiber river, the snake slithered off the ship and swam onto the island. They believed that this was a sign from Aesculapius, a sign which meant that he wanted his temple to be built on that island. This location may have been chosen for the Aesculapius Temple because it was separate from the rest of the city, which could help protect whoever was there from plague and illnesses. The island eventually became so identified with the temple it supported that it was modeled to resemble a ship as a reminder of how it came to be. Travertine facing was added in mid or late first century by the banks to resemble a ship's prow and stern, and an obelisk was erected in the middle, symbolizing the vessel's mast. Walls were put around the island, and it came to resemble a Roman ship. Faint vestiges of Aesculapius' rod with an entwining snake are still visible on the "prow". Additional Roman shrines After the Temple of Aesculapius, shrines dedicated to other deities were also erected after the 2nd century BC, namely: Jupiter Jurarius ("guarantor of oaths") Semo Sancus Dius Fidius, also a witness of oath Gaia, yet another witness of oath Faunus, boundary deity Vejovis, god of healing Tiberinus, river god Bellona, war goddess After Ancient Rome In time, the obelisk was removed and replaced with a cross-topped column. After it was destroyed in 1867, Pope Pius IX had an aedicula, called "Spire", put in its place. This monument, designed by Ignazio Jacometti, is decorated with statues of four saints related to the island: St. Bartholomew, St. Paulinus of Nola, St. Francis and St. John. Parts of the obelisk are now in the museum in Naples. In 998 Emperor Otto III had a basilica, that of San Bartolomeo all'Isola, built over the Aesculapius temple's ruins on the eastern side (downstream end) of the island. This was dedicated to his friend, the martyr Adalbert of Prague; the name of St. Bartholomew was added only later. In the early 20th century, prior to the Fascist regime's restoration of ancient place names, the Tiber Island was called the Isola di S. Bartolomeo. Likewise, Cestius' Bridge was called the Ponte S. Bartolomeo. The island is still considered a place of healing