- Video report by ITV News Correspondent Rebecca Barry
It may seem unlikely, given its themes of death, but heavy metal music is a genre providing an escape to peace for so many victims of war around the world.
Now fans of the music, including artists from Syria, have travelled to London for the first ever World Metal Congress - a celebration of the genre.
The genre was first created over half-a-century-old ago and many credit Ozzy Osbourne's Birmingham based band Black Sabbath as its pioneers.
Some of the black-clad metal devotees attending the congress are refugees who say the heavy sound of death metal helped them find solace when all else they could hear was the sound of war in their home countries.
"Many people in Syria connect metal to suicide - I think it prevented me from doing such things because it gave me strength at the worst times," says Syrian Monzer Darwish.
He added: "Without metal I have no clue what I would have done."
Jake Shuker, who is part of a band that was originally formed in Damascus, says that in a time of war, the music genre offered him peace.
"When you're hearing all these sounds, bombs, mortars, you always see blood, people getting killed," he said.
He added: "I'm a musician, what do I do?
"I grab my guitar, I grab my beer and I jam it all night."
Dr Lina Khatib, who is head of the Middle-East programme at the think tank Chatham House, says heavy metal came to her at a time when "I was a teenager growing up in Lebanon and seeking somewhere to belong".
She added: "It spoke to me as a music that commented on war, on conflict and oppression.
"I think for millions of people around the world heavy metal is an outlet for people to cope with oppression and authoritarianism."