Rome - A majestic hall at Rome's Diocletian Baths opened its doors to visitors Tuesday, after 30 years of restoration work at one of antiquity's most elaborate and spectacular thermal spa complexes.

The 40-metre-long and 25-metre-high Aula X or Hall 10, with its vaulted ceilings is one of a series of such halls - the other nine are still not accessible to visitors - that form part of the Baths first inaugurated by the Roman Emperor Diocletian in 298 BC.

Over centuries, several Roman emperors continued to expand the spa complex or Thermae from which Rome's modern day railway station Termini, situated nearby, derives its name.

The Baths today house a museum, including statues which once adorning ancient Roman tombs, while its huge frigidarium, a pool area once used by patrons to cool down after a steam bath, was converted into a Christian church, the Basilica of Santa Maria degli Angeli e Martiri in the 16th Century. (dpa)