Find out how our tunnel boring machines work and pick up your TBM licence.

Breaking news

Four huge tunnel boring machines (TBMs) have dug the twin 9km tunnels of the Metro Tunnel.

Like giant mechanical earth worms, they will chew through the rock and sand (silt) under Melbourne’s city centre. Each one weighs 1000 tonnes (that’s about 150 elephants!).

Activity

Earn your TBM licence by completing this activity.

Mastermind!

Once you’ve completed this activity, come back here to download your TBM licence (PDF, 509.8 KB). Congratulations!

Hooked on TBMs? We are!

You can find more information about Metro Tunnel tunnel boring machines including videos, images and fact sheets.