The coastal area comprises broad sandy beaches backed by dunes. Inland, most of the rivers run across the flat, fertile Flanders Plain, north-eastward to The Netherlands. In the south-east the land rises from the Sambre-Meuse valley to the highlands of the Ardennes. Here the soil is poor, and the land generally forested. The Campine coalfield is in the east. The climate is cool and wet, with warm summers.