ThevPozzuoli Cathedral site probably originated as part of the town's capitolium of the Greek or Samnite era, radically rebuilt in the Republican and Augustan eras. Between the end of the 5th and the start of the 6th century the inhabitants of the town decided to rededicate the temple as a church to Proculus of Pozzuoli. In 1538 it suffered major damage as Tripergole subsided and Monte Nuovo was formed. Bishop Gian Matteo Castaldo restored it in 1544.
Next to the church was a chapel, initially dedicated to James the Great and first built in 1354 by prince Louis of Taranto, husband of Joanna I of Naples. It was rebuilt following the eruption of Monte Nuovo in 1538 and entrusted to the confraternity dedicated to the Most Holy Body of Christ (Santissimo Corpo di Cristo), to which the chapel was rededicated at the same time. In 1817 it was annexed to the Cathedral by bishop Carlo Maria Rosini and bishop Michele Zezza linked it to the former 12th century church of Santissima Trinità.
The central nave was completely destroyed by a fire on the night of 16–17 May 1964. It broke out in the upper regions of the wooden ceiling which covered the vaulted ceiling and became so hot that it affected the stone walls and Roman marble. The paintings were saved and re-housed in the sacristy, the Santissimo Corpo chapel, the Capodimonte, the San Martino and other museums and galleries in Naples. Restoration work began under the museologist Ezio De Felice in 1968 and for the next forty years Santa Maria della Consolazione served as the city's cathedral, with San Paolo added as a co-cathedral in 1995. The 1633 bell-tower was demolished in 1968 after removing three of its four historic bells and has not yet been replaced.
The entrance is through the remains of the facade and the first two chapels of the Baroque cathedral, now presented as an uncovered narthex in front of the new glass facade, engraved with the destroyed front columns of the pronaos. Inside, it has a single nave formed of the ancient cella and pronaos, with the gaps between the columns along its long sides filled with glass. The temple floor has been raised back to its original level, creating an inclined stylobate floor with benches connecting to the chancel, which is on a lower level. This also creates space to display the archaeological remains of the Republican temple's podium in the basement. A new west-facing altar has been installed in the chancel, with an episcopal chair on the site of the old altar and a new marble ambo. The early 20th century frescoes in the choir have been restored and the paintings reinstated. The former sacristy and Santissimo Sacramento chapel have resumed their previous functions, now with a new tabernacle to the reserved sacrament.
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