The southern two-thirds of the country is called the Gutland, and is more densely populated than the Oesling. It is also more diverse and can be divided into five geographic sub-regions. The Luxembourg plateau, in south-central Luxembourg, is a large, flat, sandstone formation, and the site of the city of Luxembourg. Little Switzerland, in the east of Luxembourg, has craggy terrain and thick forests. The Moselle valley is the lowest-lying region, running along the southeastern border. The Red Lands, in the far south and southwest, are Luxembourg's industrial heartland and home to many of Luxembourg's largest towns.