The church is known as the "Palace Chapel" for being the royal chapel of the Norman Palace in Palermo. It is an old church that was built around 1080 AD, which took eight years to build. The church is considered a unique architectural masterpiece because it combines many architectural styles at the same time, including Byzantine, Roman and Fatimid. The church consists of six pointed arches, three on each side of the main facade. These sides are supported by classical columns. In addition to three hollow arches in a semicircular shape covered by a hemispherical vault, as is customary in Byzantine architecture.