wate Ichinohe tunnel in Japan ranks seventh among the
worlds longest railway tunnels. Also built as part of the
Tohoku Shinkansen railway, it has an overall length of
25.81km. Tunnel construction began in August 1991. It
was completed in 2000 and operations began in 2002.
The tunnel services were, however, suspended following
an earthquake in 2011.The tunnel design features a
single bore twin track with a horseshoe shape. It is 9.8m
wide and 7.7m high in cross section. Construction
methods used included the New Austrian Tunnelling
Method (NATM), drill and blast or mechanical excavation,
and full face or bench cut methods