Valletta is the capital of Malta, heavily fortified, it withstood numerous sieges, the last during World War Two. The island was heavily bombed by the Germans, especially Valletta and many fine buildings were destroyed, including the Opera House. The rubble from this was just levelled and left from 1941 until last year, when the government launched a project to re-build the whole area by the landward City Gate.
This area is full of buried history and I was fortunate in being granted permission to access it, before a lot was lost forever.
This is the Opera House area, which had been excavated, revealing the foundations, last seen 70 years ago! Fragments of the entrance columns also remained in situ.

General view, the gutted shops get demo'd in April

Opera House front

Remains looking towards the front

Excavated cellars, arches supported the ground floor

Rather deep

Underneath all this is the railway tunnel and station of the Malta Railway, which closed in 1931. The station buildings were next to the Opera House and destroyed along with it, but the tunnel was used as a garage until last year.
Geothermal boreholes are being sunk into its floor, to dump heat in summer and recover it in winter(clever). There are holes everywhere, a bit like gorganzola cheese, what they were for, we may never know?

Tunnel entrance, it is 56 feet wide and carried 2 metre gauge tracks

Borehole in foreground

Single track reversing 'neck' continued under the city

Holes, for what purpose?

This passage led to the booking office, blocked by war rubble

This was an unknown well, filled in, but detected and cleaned out. Dug by hand, you can still see the chisel marks!