Easdale Island, It lies off the west coast of Scotland, a few miles south of Oban. It is one of Scotland's slate islands. The ponds which dot the island are actually flooded slate quarries. Some of them are over 80 metres deep. Tens of millions of roofing slates were quarried from these pits and shipped around the world. There are Easdale slates in Australia and New Zealand. The island used to be the centre of the world's slate industry.