The magnificent Eufrazijeva Basilica is among the most perfectly preserved early Christian churches in Europe, and one of the most important monuments of Byzantine art on the Adriatic. It was built by Bishop Euphrasius in the middle of the 6th century and consists of a delightful atrium, a church decorated with stunning mosaics, an octagonal baptistery, a 17th-century bell tower you can climb (for a modest fee), and a 17th-century Bishop's Palace whose foundations date to the 6th century and whose basement contains an exhibit of stone monuments and of mosaics previously on the basilica floor. The church interior is dominated by biblical mosaics above, behind, and around the main apse. In the apsidal semidome, the Virgin holding the Christ child is seated in a celestial sphere on a golden throne, flanked by angels in flowing white robes. On the right side there are three martyrs, the patrons of Poreč; the mosaic on the left shows Bishop Euphrasius holding a model of the church, slightly askew. High above the main apse, just below the beamed ceiling, Christ holds an open book in his hands while apostles approach on both sides. Other luminous, shimmeringly intense mosaics portray further ecclesiastical themes.