Working day and night, the tunnel was constructed in just over six months.
In some cases, long tunnels were constructed to carry water into the city.
Two additional tunnels were constructed in late 1990s and early 2000s.
A tunnel was successfully constructed under the river in 2001.
This is a new tunnel, apparently constructed since we began our attack.
A tunnel was constructed in 1901 to the Castle building next door.
The tunnels were constructed at strategic points around the island.
The tunnel was constructed with a capacity for 65,000 cars daily.
For service of trains tunnels behind station have been constructed.
In the early 1990s, a tunnel was constructed linking the two buildings.