from BBC on Bosphorus Tunnel

Work starts on Bosphorus tunnel link

Construction work has started on the first rail tunnel beneath the Bosphorus Straits, linking the European and Asian sides of the Turkish city of Istanbul.
The Turkish Prime Minister, Recep Tayyip Erdogan, attended a ceremony to mark the start of digging work on the $2.5bn project.
Officials say that the tunnel, nearly 14km long, will be strong enough to resist earthquakes measuring up to nine on the Richter Scale.
It is expected to be completed within four years.
http://news.bbc.co.uk/1/hi/world/europe/3699043.stm

• It follows that Turkish PM has come back to Turkey after his trip to Western Thrace, Greece.