ITV News Wales Reporter Rhys Williams goes to Ynys Enlli, or Bardsey Island, to visit the first official 'dark sky sanctuary' in Europe
I had seen pictures of the night-sky at Ynys Enlli and knew roughly what to expect, but nothing prepared me for seeing it with my own eyes.
Known as the 'Island of 20,000 Saints', the tiny outcrop off the coast of north-west Wales has been an ancient place of pilgrimage for more than a millennium.
In medieval times, three visits to the island were considered the equivalent to a single visit to Rome.
Now it's attracting pilgrims of a different kind, who travel to Enlli, also known as Bardsey Island, off the Llyn Peninsula just to watch the stars.
Enlli is one of just 17 places around the world, and the first in Europe, to achieve global recognition for its ultra-low light pollution by being named an International Dark Sky Sanctuary.
It joins the likes of Aotea in New Zealand and the remote Pitcairn Islands in the Pacific Ocean.
The island’s unrivalled night-sky is due in part to its unique geography, with a mountain blocking all glare from mainland Wales.
In fact, the most likely form of light pollution is from Dublin.
While it is a haven for stargazers, the lack of artificial light is vital for the island’s wildlife, in particular the 20,000 nocturnal manx shearwaters which flock to Enlli at night. Too much glow can cause the nesting birds to land in the wrong place, which could prove fatal.
The island’s residents do everything they can to help, some years ago the 100-foot-tall lighthouse was re-fitted with a red light, and the handful of stone houses use only dimmed solar-powered lights.
The night-time conditions allow for some remarkable images to be captured, but light pollution from human activity is increasing significantly around the world.
As well as the affect on stargazing, there’s growing evidence of the devastating impact this has on wildlife and the natural sleep cycle of humans.
International dark sky sanctuaries are defined as the most remote (and often darkest) places in the world whose conservation state is most fragile.
The world's dark sky sanctuary locations
!Ae!Hai Kalahari heritage park (South Africa)
Aotea/Great Barrier Island (New Zealand)
Niue (South Pacific)
Pitcairn Islands (southern Pacific Ocean)
Gabriela Mistral (Chile)
Stewart Island/Rakiura (New Zealand)
The Jump-Up (Australia)
Rainbow Bridge national monument (Utah, US)
Black Gap wildlife management area (Texas, US)
Boundary Waters Canoe area wilderness (Minnesota, US)
Cosmic Campground (New Mexico, US)
Devils River State natural area, Del Norte Unit (Texas, US)
Katahdin woods and waters national monument (Maine, US)
Lost Trail national wildlife refuge (Montana, US)
Massacre Rim wilderness study area (Nevada, US)
Medicine Rocks state park (Montana, US)
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