Italian construction group Webuild is undertaking what it claims is Italy’s first excavation in a hyperbaric atmosphere, as part of the construction of the Naples-Bari high-speed railway

The new technique is being used for a 650m section of the tunnel, in a process that operates seven days a week, 24 hours a day.

The Casalnuovo tunnel is due for completion in mid-2025. It forms part of the 145km-long. €5.8 billion (US$6.3 billion) high-speed railway between Naples and Bari, scheduled for 2028.