The great façade of the Basilica of Santa Maria in Porto was built in the 16th Century and was modified by the architect Camillo Morigia in the latter half of the 18th Century. The interior is solemn and imposing, divided into nave and two aisles with a very wide transept topped by a high cupola. In the left wing is a marble bas-relief depicting the Virgin Mary in an attitude of prayer and the so-called Greek Madonna. Tradition says that it had arrived miraculously from Constantinople.