Lauder – the town lies in the valley of the Leader Water surrounded by hills made of greywackes (pronounced greywackies) which are a type of sandstone largely composed of sand grains of grey or green rock fragments deposited in deep marine trenches close to volcanic mountain ranges. Greywackes quarried nearby have been used in the old buildings in Lauder by stone masons who were clearly very skilful. The greywackes are of Silurian age, about 430 million years old.