Anglesey, Gwynedd and Conwy have darkest skies in Wales

It reveals that more than 68 per cent of the country falls within the two darkest ‘night sky categories’. This includes 95 per cent of Areas of Outstanding Natural Beauty and national parks.

The areas of the country with the darkest night skies were Anglesey, Gwynedd and Conwy, while Newport, Cardiff and the Vale of Glamorgan had the lightest.

However, there was evidence that the amount of light emitted in cities is decreasing.

The map was commissioned by Natural Resources Wales. It uses satellite imagery of Wales taken at 1:30am.

Jill Bullen, an advisor for Natural Resources Wales, said: “Dark skies can affect our experience of nature and landscapes and can benefit our health and wellbeing and local wildlife.

“Although dark skies are most often experienced in rural areas, our experience of the night sky can be enhanced in towns by reducing light pollution and using dark sky friendly lighting.”

Natural Resources Wales has produced a map showing Wales' darkest, and most light polluted, areas

Natural Resources Wales believes identifying the areas with little light pollution will enable them to promote its benefit and ensure the consideration of light pollution in future developments.

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Ms Bullen added: “Lighting kept on for longer than it is needed or units that spill light upwards, rather than to where it is most needed, contribute to sky glow and light intrusion.

“Many local authorities now have energy saving policies in place, with lights being dimmed, part night lit or switched off through the night where it is possible and safe to do so.”

International Dark Sky Week is April 5 to 12.

It’s held during the week of the new moon, when the sky is naturally at its darkest.