Categorized by geological and physical attributes, they are the Northeastern Highlands, the Green Mountains, the Taconic Mountains, the Champlain Lowlands, and the Vermont Piedmont.
years ago, the second mountain building period created Green Mountain peaks that were 15,000–20,000 feet (4,600–6,100 m) tall, three to four times their current height and comparable to the Himalayas.
The rural northeastern section known as the "Northeast Kingdom" often averages 10 °F (5.6 °C) colder than the southern areas of the state during winter.
states of Massachusetts to the south, New Hampshire to the east, New York to the west, and the Canadian province of Quebec to the north.In the northwest, near Lake Champlain, is the fertile Champlain Valley. Several mountains have timberlines with delicate year-round alpine ecosystems, including Mount Mansfield, the highest mountain in the state; Killington Peak, the second-highest; Camel's Hump, the state's third-highest; and Mount Abraham, the fifth-highest peak.The most populous city in Vermont is Burlington, and its metropolitan area is also the most populous in the state with an estimate of 214,796 as of 2013.The geological pressures that created those peaks remain evident as the Champlain Thrust, running north–south to the west of the mountains (now the eastern shore of Lake Champlain).It is an example of geological fault thrusting where bedrock is pushed over the newer rock formation.