Amman's vast Roman theater is the most obvious relic of the ancient city of Philadelphia. It was originally built in the 2nd century BC against the slope of a hill, to hold about 5,000 spectators. The theater's orientation is said to be almost perfect, providing a minimum of sunlight in the spectators eyes. Concerts and performances are still held here. Considerable restoration has been done to the theater. In front of the theater are the remains of the Roman forum, most notably, the long colonnaded path. There are two museums built into the foundations of the theater, opposite one another: the Folklore Museum and the Museum of Popular Traditions; if you're choosing one or the other, the latter is generally considered more interesting.