If you live in a big city, living life without public transportation can be a nightmare! Many people do not own vehicles, and riding your bicycle to get everywhere can be extremely hard. Luckily, this is what public transportation was invented for! Probably the most effective way of transportation is the subway! A lot of people use the subway on a daily basis, but only some have wondered how the tunnels are actually made! Wonder no more, because we have two videos that will provide you with an answer! These footages show the tunnelling machines used for boring tunnels! The presented tunnelling machines are ENORMOUS, and can bore through gravel, boulders and clay with ease! The tunnelling devices are actually called Tunnel Boring Machines, or TBMs. The two videos feature tunnel boring machines being used in London and New York City. The tunnel boring machines in London are owned by Crossrail, a company that plans a new railway line in the capital of the United Kingdom.