Police are warning Bristol Airport travellers to expect delays ahead of a planned protest by Extinction Rebellion.
More than 1,000 activists are expected to meet at the airport this afternoon to protest expansion plans.
The group says it plans to don green capes and cycle around the airport to music.
A Facebook page promoting the event reads: "Incredibly, despite being one of the first councils to declare a climate emergency, Bristol City Council is backing expansion plans at Bristol Airport.
"Air travel is hugely carbon-intensive. We need to scale it back, not increase it. So on Saturday, Wiveliscombe and Taunton Extinction Rebellion groups are joining up with the Bristol groups to cycle around Bristol Airport, to ask for a re-think.
"There will be in excess of 1,000 cyclists all wearing green capes, and enjoying some cycling-themed music. It will be a joyous occasion, it will be a celebration of cycling and of life."
Extinction Rebellion closed one of the main roads through Cardiff for three days in July, when they blocked Castle Street in Cardiff in a bid to increase pressure on the government to reduce greenhouse gas emissions.
Avon and Somerset police say the event may lead to congestion on area roads.
A spokesperson for the force said: "We are aware of a potential protest taking place in the vicinity of Bristol Airport on Saturday 14 September from 11.30am until 2.30pm.
"Passengers are advised to allow extra travel time in case of congestion on local roads."
