It numbers among its chambers the Gothic hall of Giovanni Pisano in which Celestine V.
The cathedral of St Januarius, occupying the site of temples of Apollo and Neptune, and still containing some of their original granite columns, was designed by Nicola Pisano, and erected between 1272 and 1316.
Some statuettes and sculptured slabs partly belonging to its pulpit, perhaps the work of Andrea Pisano, have been found; upon the reverse side of two of the slabs are still older reliefs of the 8th or 9th century; so that the slabs perhaps originally came from Tharros.
At about the same time Niccola Pisano (d.
During the 13th and 14th centuries in Italy the widespread influence of Niccola Pisano and his school encouraged the sculptor to use marble rather than bronze for his work.