Protest group Extinction Rebellion started their five day protest in the streets of Bristol this morning [15 July].
The climate change collective are campaigning for the government to lower its 2050 goal for zero carbon emissions to 2025.
Some protesters were seen camping overnight in Castle Park in the city centre ahead of the action beginning today.
Campaigners held back traffic at the one of Bristol's busiest roundabouts, the Bearpit, on Monday afternoon.
One of the city's congestion hotspots, Bristol Bridge, is another main target for protesters. Bristol City Council closed the bridge to traffic earlier today, but it is still accessible to pedestrians and bicycles.
Avon and Somerset Police will have an around-the-clock presence for as long as the protests last, with more than 1,000 people expected to take part.
Bristol City Council say they are trying to keep disruption to a minimum but have been working with protestors to 'ensure there is fair a balance between our legal obligation for people’s right to peaceful protest and our need to keep the city moving.'
First Bus have warned passengers to expect delays throughout the week, as many of their services will need to be redirected through the city centre.
West Country activists acting on behalf of the group have brought parts of the city to a halt in the past to draw attention to their cause, as well as shutting down major roads in London as part of a wider protest.