Inside the basilica (above)

One usually enters the church through the portal on the right and, once inside, walks to the left towards the centre of the church. From this standing point, it is possible to appreciate a general, overall view of the Basilica. Glancing up towards the ceiling, one can admire the grandiose paintings completed by Carlo Rosa of Bitontum between 1661 and 1671 (in the central nave area, scenes inspired by the life of the Saint depict the liberation of Adeodatus (the Basil of the original Greek texts) and his reunion with his parents, as well as the salvation of the sailors and the Council at Nicaea. Then, shifting one’s gaze up laterally, one can view the “Matrons’ Gallery”, to which the hexabored gallery corresponds externally. Further down, one can observe the three, large, transversal arches built in 1458 and 1494 (the latter, built by Ludwig the Moor, Duke of Milan and Bari), to reinforce the structure following the terrible earthquake of 1456. The wooden pulpit, built in the 17th century, can also be admired.
After taking a quick glance at the Treasure Hall situated in the bell tower, one can proceed down the right nave and take the staircase which leads down to the crypt. On the right hand side of the landing, just before entering the crypt, lies the sarcophagus of the Abbot Elias, with its beautiful epigraph comparing him to Salomon and the prophet Elijah, as well as the four philosophers engaged in conversation.
The church as we see it now is the consequence of the radical restoration of the years 1925-1934, when (with the exception of the pulpit, and the ceiling of Carlo Rosa 1661) everything that was built after XVI century was removed (the three huge archs connecting the central nave were built in the second half of XV century after an earthquake) . Previously, the walls were full of decorated chapels.

Right nave. Entering the church through the right entrance, soon at left: picture of St. Jerome, patron of catholic schools.
At right: treasury Hall with painted manna bottles and russian gifts (at left), ex voto and precious relics (in front), Norman and Anjou gifts (at right). 
Ahead: Door to the inner court. Epigraph of the Fascist period.
Right Transept: Silver altar with scenes of St Nicholas life (1684, transformation from an ancient silver altar of the serbian zar Uroš II Milutin, 1319); triptich of Andrew Rizo of Crete (1451); fresco of the Crucifixion of John of Taranto in the chapel of St Martin (1304). 
Presbyterium. Mosaic floor of the year 1000, with a decoration repeating the monogram  “Allah is great”. Cyborium covering the main altar (beautiful norman capitals). The episcopal throne of Abbot Elia, builder of the church (1098), considered one of the best and most ancient romanesque scultures in the world. In the apse: Mausoleum of Bona Sforza, queen of Poland and duchess of Bari (+1557).
Left Transept. Painting of Bartolomeo Vivarini, showing the Virgin with the Child and Saints (1476); Musical Organ.
Left Nave: Statue of St Nicholas (1794). The 9^th of May is brought on the sea on two ships, to be venerated by pilgrims.