The Pantheon, “All God”, is one of the best preserved Roman buildings. A temple had been on the site for many years but the one visible today is that designed by the Emperor Hadrian, and built in 126AD. The building was converted to a Christian church in the 7th century, but can still be enjoyed in something like its original form. The front of the building resembles a classic Roman temple portico, supported by columns. Roman temples, for the main part, were to be enjoyed from the outside. The Pantheon is different – it can only be appreciated from inside. Behind the portico is the rotunda, a round space, under the largest dome built by the ancients. Set in the center of the dome is a circular hole, the oculus. The oculus is the only source of light and is an elegant allegory of God. At no time will the light ever touch the floor, as if to say that all we can know of God is by indirect means.