Record numbers of people are expected to attend the 133rd Durham Miners' Gala.
It is thought that around 200,000 people will turn up at the political gathering to celebrate Labour leader Jeremy Corbyn's performance in the General Election.
Corbyn will make a speech this afternoon but has already been photographed standing on a platform in the city as brass brands and supporters holding colourful banners march beneath him.
The historic event, also known as the big meeting, is the UK's biggest celebration of trade unionism, and is marked with guest speakers, brass bands and the parading of colourful pit banners.
This years event, organised by the Durham Miners' Association, will see film director and activist Ken Loach, along with shadow education secretary, Angela Rayner and union bosses, share Corbyn's platform.