VTVermont Geography

New Hampshire owns the entire Connecticut River

Most river boundaries run down the middle of the channel. Vermont's eastern boundary does not. It sits at the low water mark on the Vermont bank, which means the whole width of the Connecticut River, bank to bank along the entire shared boundary, belongs to New Hampshire. The reason goes back to a 1764 order of King George III fixing New Hampshire's western limit at the west bank of the river, and the Supreme Court confirmed the arrangement in 1933 after Vermont argued for the usual midpoint rule and lost. A Vermonter wading in ankle deep is standing in another state. Vermont is also the only New England state with no Atlantic coastline at all, and the only state in the region whose largest lake drains into Canada.

A ridge with a face on it

The Green Mountains run the full length of the state as a single spine rather than a scatter of peaks. Mount Mansfield, 4,393 feet, is the highest, and seen from the east its skyline reads as a human profile lying on its back, which is how its features got named: the Forehead, the Nose, the Chin and the Adam's Apple. The Chin is the true summit. Camel's Hump, 4,083 feet, is the more recognisable outline because its top was burned clear and stayed bare. Above treeline Vermont holds only a few hundred acres of alpine tundra in total, spread across Mansfield, Camel's Hump and Mount Abraham, and the plants growing there are arctic relicts left behind when the ice retreated. The Long Trail follows the ridge for 272 miles from the Massachusetts line to the Quebec border. Work started in 1910 and finished in 1930, making it the oldest long distance hiking path in the country, and the Appalachian Trail borrows its southern hundred miles.

Water leaves Vermont in three directions

That spine is a watershed divide, and it sends the state's rivers to three different destinations. On the western side the Winooski, Lamoille, Missisquoi and Otter Creek run into Lake Champlain, which flows north down the Richelieu into the St. Lawrence and out past Quebec City. On the eastern side the White, Ottauquechee, West and Passumpsic feed the Connecticut, which reaches Long Island Sound. In the northeast corner the Clyde, Barton and Black rivers empty into Lake Memphremagog, which straddles the international line and drains through the St. Francis, also to the St. Lawrence.

Three of those rivers do something unusual. The Winooski, the Lamoille and the Missisquoi all cut clean through the Green Mountain range instead of going around it, because they were established on an older land surface and kept sawing downward while the mountains rose beneath them. Otter Creek, at about 112 miles, is the longest river lying entirely inside the state.

The sea that used to be here

Lake Champlain is roughly 120 miles long and about 400 feet deep at its deepest, and its surface, near 95 feet above sea level, is the lowest ground in Vermont. In 1849 railway workers digging near Charlotte, about ten miles from the lake and 150 miles from any ocean, uncovered the skeleton of a beluga whale in blue marine clay. It was not a hoax. The weight of the ice sheet had pressed the St. Lawrence lowland below sea level, and when the ice withdrew salt water flooded in from the Atlantic, creating the Champlain Sea from roughly 13,000 to 10,000 years ago. The land has been rebounding ever since.

Older evidence sits on the Burlington waterfront at Lone Rock Point, where the Champlain Thrust has shoved 500 million year old Dunham Dolomite bodily on top of 450 million year old Iberville Shale. Older rock resting on younger rock is one of the clearest field demonstrations of thrust faulting in North America, and you can walk to the contact. As for the lake itself, a line inserted into a federal bill in 1998 briefly listed Champlain as a Great Lake. The provision was repealed within weeks.

The 45th parallel and a survey nobody fixed

Vermont's northern boundary is meant to be the 45th parallel, the halfway point between the equator and the North Pole. John Collins and Thomas Valentine surveyed it between 1771 and 1774, and their line drifted as much as three quarters of a mile north of the true latitude. When Britain and the United States finally settled the northeastern boundary in the Webster-Ashburton Treaty of 1842, they chose to keep the old marks rather than re-run the line, so Vermont holds a strip of ground that trigonometry would hand to Quebec. The best known casualty of the error stands just over the New York line at Rouses Point, where an American fort begun in 1816 turned out to be on Canadian soil and earned the nickname Fort Blunder.

The state itself is a wedge, about 90 miles wide along the Canadian line and only about 41 miles wide where it meets Massachusetts. Winters in the interior are severe: Bloomfield recorded 50 below zero on 30 December 1933, while the state's hottest reading, 107 degrees, came at Vernon in the Connecticut valley on 4 July 1911. About three quarters of the land is forest today, which is a recovery rather than a constant. The merino sheep boom had stripped the hills bare by the middle of the nineteenth century, when Vermont counted more than a million sheep, and the woods grew back only after the farms failed.

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