On: Tunnel Boring Machines (2018)

[Swannie]

> Which would require the digging of a third hole where the TBM "drill heads" meet.

In most projects it's called a station.

http://www.crossrail.co.uk/construction/tunnelling/meet-our-...

Occasionally you'll have dive sites that are not at/near stations, but not that often.

https://www.sydneymetro.info/station/blues-point-temporary-r...

https://www.sydneymetro.info/tunnelling