All of West Virginia is part of the Appalachian Mountain system. The land is rugged, ranging from hilly to mountainous, and there are no large areas of flat land. West Virginia can be divided into two geographic areas – the Appalachian Plateau and the Ridge and Valley Province. The Appalachian Plateau takes up the western two-third of the state. The eastern part of the Plateau is called the Alleghany Mountain section. This area has more than 40 peaks over 4,000 feet (1,200 meters) including Spruce Knob, the highest point in the state (4,863 feet/1,482 meters). It is divided from the Ridge and Valley Province by the Allegheny Front, an area of hills and mountains which divides the waters that flow to the Atlantic Ocean from those flowing to the Gulf of Mexico. The Ridge and Valley province is famous for its folded mountains, which are part of the chain reaching from Canada to north-central Alabama. The lowest point in the state is 247 feet (75 meters) above sea level at Harpers Ferry, which is located on a steep strip of land rising above the meeting of the Shenandoah and Potomac rivers.

Millions of years ago, all of West Virginia was under water. These waters receded, leaving an area of rock and coal that has gradually been worn down. Today, rivers have carved deep valleys and gorges all through West Virginia, giving the land a rugged character. Most of the rivers and streams in the Ridge and Valley province in the eastern part of the state flow into the Potomac River. The streams in the Allegheny Plateau section mostly flow into the Ohio River and its tributaries—the Monongahela, Little Kanawha, Kanawha, Guyandotte, and Big Sandy. Underground streams have also carved out many caverns—including Seneca Caverns, Smoke Hole Caverns, and Organ Cave—from the limestone rock. West Virginia has no natural lakes.

West Virginia has a humid continental climate, with hot summers and cool to cold winters. January is the coldest month, with average temperatures around 33°F (1°C). July is the warmest month, with average temperatures of around 73°F (23°C). Rainfall varies from more than 60 inches (1,520 mm) in the mountains areas to 35 inches (890 mm) in the rain shadow areas east of the mountains. Around 20 inches (510 mm) of snow falls each year in the southwest, and more than 64 inches (1,620 mm) falls in the eastern mountains. The highest recorded temperature, 112°F (44°C), was at Martinsburg on 10 July 1936; the lowest, –37°F (–38°C), at Lewisburg on 30 December 1917.