Since 1986 Gravina Cathedral has served as a co-cathedral of the Diocese of Altamura-Gravina-Acquaviva delle Fonti. It was built here at the end of the 11th century by Humphrey of Hauteville, Count of Apulia and Calabria, and thus lord of the town. This church was destroyed in the years 1447-1456 by a fire followed by an earthquake, after being refurbished in a Renaissance-Romanesque style. Of the original church only a few Byzantine capitals and frescoes remain. The present cathedral was built in the thirty years following, under the supervision of the bishop Matteo d'Aquino.
The main façade has a large rose window. The altarpieces are made from 17th-century intarsia with polychrome marble and mother of pearl. The ceiling has framed canvases. The church has an altarpiece carved in Bitonto stone (1468) by Guido da Guida. There is a San Michele (1538) carved in mazzaro, a local stone, and attributed to Stefano da Putignano. Along the north nave is a Byzantine fresco of the Madonna del Piede. The oak choir-stalls were made in the 15th century and rebuilt by Bishop Antonio Maria Manzolio (1581-1593).
The adjacent sacristy has a ceiling refurbished by bishop Manzolio, and elaborate presses. The bell-tower was built from a Norman watch tower.
References:Celje Castle was once the largest fortification on Slovenian territory. The first fortified building on the site (a Romanesque palace) was built in the first half of the 13th century by the Counts of Heunburg from Carinthia on the stony outcrop on the western side of the ridge where the castle stands. It had five sides, or four plus the southern side, which was a natural defence. The first written records of the castle date back to between 1125 and 1137; it was probably built by Count Gunter. In the western section of the castle, there was a building with several floors. Remains of the walls of this palatium have survived. In the eastern section, there was an enclosed courtyard with large water reservoirs. The eastern wall, which protects the castle from its most exposed side, was around three metres thicker than the rest of the curtain wall. The wall was topped with a parapet and protected walkway.