The Big Sleep Out will come to Cardiff this December to raise money for homeless and displaced people in Wales and across the world.
For one night only, an estimated 50, 000 people will sleep outside in iconic locations across the globe for the same cause - including some famous faces.
Here is everything you need to know about getting involved and what to expect at the Cardiff event.
Where and when is it happening?
Cardiff Castle will open its doors at 6pm on Saturday, December 7 . The event begins with a choir performing as people enter the venue.
At 7pm, there will be an opening speech from Wales' First Minister, Mark Drakeford, shortly before a young person talks about their experience of homelessness.
There will then be a host of entertainment - see below for details - before a bedtime story at 10.30pm. The sleepover ends at 6am the following day.
Who is is raising money for?
The event, hosted by homeless charity Llamau, in partnership with the World's Big Sleep Out and Social Bite, is part of a global showing of solidarity with those experiencing homelessness and displacement.
All funds raised will go towards homelessness charities - 50% of the funds will go to Welsh homeless charities and 50% will go to global charities such as Unicef USA, Malala Fund and the Institute of Global Homelessness.
Who are the famous supporters?
Gavin & Stacey star Ruth Jones will officially close the night and she will read a bedtime story to those taking part in the challenge.
Ruth said: “Wherever you seem to go, especially in Cardiff, you’re faced with the very harsh reality of homelessness. It’s so sad to see so many people struggling with homelessness every day.
"Nobody should ever find themselves without a home. That’s why I want to show my support at the World’s Biggest Sleep Out this year.”
Singer-songwriter Charlotte Church will also perform at the event.
Charlotte will be performing on the night in collaboration with the incredible ParaOrchestra, the world’s only large-scale ensemble for professional disabled musicians.
She said: “Homelessness is so prevalent today, especially through the streets of Cardiff.
"It’s really shocked and saddened me and to know young people could be sleeping outdoors in such freezing conditions is incomprehensible."
Ruth and Charlotte will be joined by Boy Azooga, Kizzy Crawford, Shelleyann Evans, The Gentle Good, Patrick Jones and Dr Beverley Ballcrusher.
How can you take part?
Registration is open now, and Llamau is asking everyone taking part to commit to raising £150.
You’ll be helping to raise lifesaving funds for a targeted one million homeless and displaced people across Wales and throughout the world.
You can register for the Cardiff event here .
