The town of Taposiris Magna, known in Arabic as Abu Sir, was founded in around 280–270 BCE by Ptolemy II Philadelphus about 45 kilometers to the west of Alexandria along the northern shore of Lake Mareotis. Its great temple, of which only the impressive outside walls remain standing today, was once an important cult center of the gods Osiris and Isis. However archeological finds, including over one hundred Doric column drums discovered on site, have shown that the temple of Taposiris Magna had a unique combination of both Egyptian and Greek temple architecture. Thus, within the typical Egyptian-style pylon and surrounding walls, once stood a Hellenistic sanctuary with Doric columns. Opposite the temple, stands the stone tower built in Greco-Roman times, known today as Borg El Arab. This tower, which is a small replica of the ancient Pharos of Alexandria, is thought to have been a watch tower or a lighthouse.