Anywhere really. These started off in the US in 1972 as a gathering of the [hippie] tribes and have spread around the world as a celebration of the joy of life in the cathedral of nature,one month of sharing and giving and living communally, around the lunar cycle.. The biggest are in the US, but equally interesting are those in Europe, the Canary Islands, Russia, South America and Australasia just to name a few. The later are much smaller, 200-300, and more intimate : the American rainbow can have up to 20,000 attending. These events are clothes optional. This quote from a NZ document expresses the sentiment well: "Many like the feeling of freedom. Others see in nudity a spiritual component. Either way here we are creating an Eden where you can be naked without shame. This doesn’t mean you can’t wear clothes, you just don’t have to." In practice the amount of nudity varies enormously being more linked to ceremonies but there are those who choose to go about naked in general.
It's just called Roskilde Festival. It's the biggest music festival in northern Europe
Which festivals in UK would you recommend from experience or heard of?
I've seen showers exactly like that at Isle of Wight festival in the UK, but the showers themselves are probably moved from one festival site to another throughout the summer so would probably be hard to say for sure, unless someone recognises something specific in the photo.
