In 324 AD, the former Basilica was constructed over the tomb of Apostle Peter in the southeast of the Vatican City under the order of Emperor Constantine. It was broken down by the reason of decrepitude once, but re-construction started in 1506, and the Basilica in the baroque architecture that stands today completed in 1624. The main characteristics are the dome-shape design and the cross installed at the height of 136m. It is the head church of the Catholics at present. The plaza in front of the Basilica is surrounded by 284 semi-circular pillars and an obelisk stands in the center of the plaza.