Vermont has seven geographic regions, but most of the state is made up of either mountains or valleys. The Green Mountains cover most of the state. They stretch from the Canadian border to the Massachusetts state line. The Green Mountains contain Vermont’s highest peaks, including Mount Mansfield (4,393 feet/1,340 m), the highest point in Vermont; Killington, 4,235 ft (1,293 m); and Elbow Mountain (Warren), 4,135 ft (1,260 m). A much lower range, the Taconic Mountains, straddles the New York-Vermont border for about 80 mi (129 km). To the north of the Taconic Mountains is the narrow Valley of Vermont; farther north is the Champlain Valley, a lowland between Lake Champlain (the state’s lowest point, at 95 feet/29 m above sea level) and the Green Mountains. The Vermont Piedmont is a narrow corridor of hills and valleys stretching about 100 mi (161 km) to the east of the Green Mountains. Two smaller mountain ranges are also in the state - the Northeast Highlands, an isolated series of peaks near the New Hampshire border; and the Hoosac Range on the Vermont-Massachusetts border.

Vermont’s largest rivers are the Winooski, Lamoille, and Missisquoi rivers, which all flow into Lake Champlain. Lake Champlain’s waters, in turn, empty into Canada’s Richelieu River and then flow into the St. Lawrence. The longest river entirely within the state is the Lamoille (85 miles/135 km), followed by Otter Creek (75 miles [120 km]). Several small streams also flow from the central highlands into the Connecticut River. The largest of these is the White River. Vermont also includes around three-fourths of Lake Champlain (the western portion of is in New York, while one-fourth of Lake Memphremagog—lies in Canada. There are 400 natural lakes in Vermont. The largest is Lake Bomoseen, west of Rutland.

Vermont has a continental climate, with warm summers and cold winters. Winter temperatures can drop to −34 °F (−37 °C) and lower, and summer temperatures rarely rise above 90 °F (32 °C). Pleasant summer days often turn cool after nightfall. The record high temperature for the state is 105°F (41°C), registered at Vernon on 4 July 1911; the record low, –50°F (–46°C), at Bloomfield, 30 December 1933. Snowfall averages between 70 and 80 inches (1,800 and 2,000 mm) in the valleys and up to 110 inches (2,800 mm) in the mountains. Yearly rainfall is from 34 inches (870 mm) in the eastern and western regions to more than 40 inches (1,025 mm) in the mountains.