Many are in their late teens and early 20s, and are willing to take radical action and risk arrest to put an end to our dependence on oil.
Campaigners are adamant that they'll defeat the high-speed rail project, despite the High Court ruling in favour of their eviction.
Anti-HS2 demonstrators at Euston say that they are being subjected to "torture" by bailiffs.
Four young Extinction Rebellion protesters tell us why getting nicked is worth it.
The London mayor wants to create a new road tunnel in London despite announcing his plans to tackle climate change.