The Cathedral of Saint Andrew or Cathedral Church of Saint Andrew is a Greek Orthodox basilica in the west side of the city center of Patras in Greece. Along with the nearby old church of St. Andrew, it constitutes a place of pilgrimage for Christians from all over the world. It is dedicated to the First-called Apostle of Christ, Saint Andrew. Construction of the Greek Byzantine-style church began in 1908 under the supervision of the architect Anastasios Metaxas, followed by Georgios Nomikos. It was inaugurated 66 years later, in 1974. According to University of Patras professor Ch. Apostolopoulos who has extensively studied the church building, the church has a surface area of 1,900 m2 on the ground floor and additionally 700 m2 on the first level (used as a gynaeconitis). The church has a length of ~60 m, width ~52 m and has a capacity of 7,000 people. Other sources give similar numbers for the size of the surface area (there are different numbers depending on the inclusion or not of the first level). It is the largest church in Greece and the third largest Byzantine-style church in the Balkans, after the Cathedral of Saint Sava in Belgrade and Alexander Nevsky Cathedral in Sofia. Over the central dome there is a 5-meter-long, gold-plated cross and over the other domes, there are 12 smaller crosses. These crosses symbolize Jesus and His apostles. The interior of the church is decorated with Byzantine-style wall paintings and mosaics.
Relics of the apostle Saint Andrew are stored in the church. They consist of the small finger, part of the top of the cranium of the Apostle, and small portions of the cross on which he was martyred, all kept in a special shrine. The holy skull of the Apostle was sent there from St. Peter’s Basilica, Rome in September 1964, on the orders of Pope Paul VI. Cardinal Bea led the party of 15 cardinals that presented the relic to Bishop Constantine of Patras on 24 September 1964. Thousands of people (among them prime minister Georgios Papandreou) and many Greek Orthodox bishops participated in the reception ceremony of the skull. After a procession through the streets of the city, the skull was placed in a special silver miter inside the church. The cross of St. Andrew was taken from Greece during the Crusades by the Duke of Burgundy. Parts of the cross were kept since Middle Ages in the church of St. Victor in Marseilles. They were returned to Patras on 19 January 1980. The cross of the apostle was presented to the Bishop of Patras Nicodemus by the Roman Catholic delegation led by Cardinal Roger Etchegaray.