You enter the sanctuary through a large passage flanked by arches to the west (a monumental quadruple arch from the time of Hadrian leading directly to the Saepta Julia) and to the east, leading to the Via Lata. The eastern arch was built to commemorate Vespasian's and Titus's joint triumph over Judaea in 71 CE; this arch is depicted in the reliefs on the funeral monument of the Haterii family. You crane your neck upward to see the towering obelisk brought from Egypt by Domitian that stands in the center of this passage. You turn your head to the north, where the smell of exotic incense and the sound of chanting and bronze rattles draws your attention to a very large, rectangular courtyard with two temples at the far end. Turning to the south, in contrast, presents the lovely vista of a semi-circular portico surrounding a deep basin filled with water.
As you gaze at this impressive complex, you find it hard to credit the story that Tiberius ordered the sanctuary destroyed in 19 CE because of scandal and had its cult statues thrown in the Tiber. However, the cult of Isis grew in popularity and later emperors rebuilt the complex. In 71 CE Vespasian and Titus spent the night in the Temple of Isis as they awaited their triumph, so this sanctuary was greatly favored by the Flavian emperors. When it burned down in a great fire of 80 CE, Domitian rebuilt it in its present splendid form.