Trevor Fishlock explores how two sisters from Wales, Gwendoline and Margaret Davies, created one of the great British art collections of the 20th century. They embraced impressionist art long before it became fashionable and left their remarkable collection to the nation. The money came from the coalfields of South Wales, making the sisters two of the richest women in the world. During the First World War they worked as volunteers in a soup kitchen just behind the front line. All their lives, they never gave up on their desire to turn their home at Gregynog into the beating artistic and cultural heart of Wales.