Cripta di Santa Restituta

Virtually next door to the Chiesa di Sant'Efisio is the Cripta di Santa Restituta, which has been in use since pre-Christian times. It's a huge, eerie natural cavern where the echo of leaking water drip-drips. Originally a place of pagan worship, it became the home of the martyr Restituta in the 5th century and a reference point for Cagliari's early Christians. The Orthodox Christians took it over - you can still see remnants of their frescoes - until the 13th century, when it was abandoned.

In WWII it was used as an air-raid shelter, a task it was not up to, since many died while holed up here during a raid in February 1943. It's interesting to make out the wartime graffiti that covers the walls.