Hundreds of people have gathered across Wales to join millions around the world calling for action on climate change.
Children and young people walked out of schools and lectures, with hundreds of thousands of workers expected to join them.
The protests are part of a snowballing movement sparked by teenage activist Greta Thunberg’s school strikes outside the Swedish parliament.
It comes ahead of a climate action summit in New York convened by UN secretary general Antonio Guterres to urge countries to up their climate efforts.
The demonstrations in Cardiff are one of 11 protests across Wales.
Students from St Joseph's School in Port Talbot tweeted a video saying they are on their way to the climate strike in Swansea.
The protest in Wales comes following demonstrations at the Valero oil refinery in Pembrokeshire, where Extinction Rebellion activists blocked the entrance to the site.
They told ITV News the government and big business "are not moving away from fossil fuels fast enough."
The UK Student Climate Network (UKSCN) says more than 200 events are taking place across the UK, with – for the first time – adults being encouraged to join the youngsters as they strike.
UKSCN is calling on politicians to bring in a “Green New Deal” to cut the UK’s emissions to zero and improve lives, changes to education to equip youngsters to deal with the climate crisis and votes at 16 to give them a voice.
Alex Edwards, Welsh Youth Strike For Climate said it is the "youngest generations who will have to suffer the greatest impacts of climate change".
Worldwide, there are more than 4,600 events in 139 countries taking place as part of the Fridays for Future movement.