Coll's combination of very low population, no street lighting outside the village, and an exposed mid-Atlantic position gives it some of the darkest skies in the UK. The Dark Sky Community status is taken seriously — even the new bulbs at the pier are warm-coloured and shielded — and the island runs a small Dark Skies Festival in the autumn.
The best viewing months are October to March, when the nights are long and the air is dry. Bring binoculars or a small telescope; the Coll Bunkhouse and several of the self-catering cottages can lend you one. On the right night you may also see the aurora — Coll is at the same latitude as Juneau, Alaska.