MNMinnesota Geography

The Northwest Angle, a rectangle created by a bad map

Hanging off the top of Minnesota is a block of land about 123 square miles in size that cannot be reached from the rest of the United States without either crossing Lake of the Woods by boat or driving roughly 60 miles through Manitoba. The Northwest Angle reaches 49 degrees 23 minutes north, making it the northernmost land in the contiguous 48 states, and about 120 people live there. Its border post at Jim's Corner is an unstaffed shed with a videophone; travellers call in their own arrival.

It exists because of a geography error written into the 1783 Treaty of Paris. Working from John Mitchell's 1755 map, the negotiators ran the boundary west from Lake of the Woods to the source of the Mississippi, assuming the river rose somewhere north and west of the lake. It does not. It rises about 150 miles to the south. The 1818 Convention patched the gap by drawing a line from the northwesternmost point of Lake of the Woods due south until it struck the 49th parallel, then west along the parallel to the Rockies. That short due-south segment is the eastern edge of the Angle, and it left a piece of American territory stranded above Canadian land.

Rain that leaves for three different seas

Minnesota sits on a triple watershed divide. Water falling on the north slope runs through the Red River of the North and the Rainy River into Lake Winnipeg and out to Hudson Bay. Water falling on the eastern slope reaches Lake Superior and travels the Great Lakes and the St. Lawrence to the North Atlantic. Water falling on the southern slope enters the Mississippi and reaches the Gulf of Mexico. The three-way junction is on the Laurentian Divide in the Iron Range country north of Hibbing, and Minnesota is the only state whose drainage splits between those particular three outlets.

The Mississippi begins at Lake Itasca in Clearwater County at 1,475 feet, identified in 1832 by Henry Schoolcraft with the Ojibwe leader Ozawindib guiding him to it. Schoolcraft coined the lake's name by splicing the middle syllables out of the Latin veritas caput, true head. At the outlet the river is about 18 feet across and shallow enough to wade, and stepping stones let visitors cross it. It travels 2,340 miles from that spot to the Gulf.

Thirteen miles between the highest and lowest ground

Eagle Mountain in Cook County tops out at 2,301 feet. Lake Superior, at 601 feet, is the state's lowest point, and it lies roughly 15 miles away. Few states pack their vertical extremes so close together. The drop happens across the Sawtooth Mountains along the North Shore, where basalt lava flows erupted 1.1 billion years ago during the Midcontinent Rift tilt downward toward the lake and break off in cliff faces at Palisade Head and Shovel Point. That same rift is why the North Shore has hard rock, waterfalls at every river mouth and agate on its beaches, while 200 miles southwest the ground is soft glacial till.

11,842 lakes, and the corner that has none

The licence plates say 10,000 lakes. The Department of Natural Resources counts 11,842 of at least ten acres, and the total shoreline of Minnesota's lakes and rivers runs to roughly 90,000 miles, more than California, Florida and Hawaii combined. Almost all of it is glacial work: kettle holes where buried ice melted, basins dammed behind moraines, and in the northeast, rock hollows gouged straight out of the Canadian Shield, which is what the Boundary Waters Canoe Area Wilderness is. That wilderness covers 1,090,000 acres and more than 1,100 lakes, motors are barred from most of it, and portage trails between the lakes follow routes the voyageurs used.

The exception is the southeast. Winona, Wabasha, Fillmore and Houston counties fall inside the Driftless Area, a region the last ice sheet flowed around rather than over. With no till and no kettles there are almost no natural lakes there. Instead the Mississippi runs between limestone bluffs 500 feet high, and the uplands are riddled with sinkholes, disappearing streams and cold spring-fed valleys that hold the state's trout water.

A river running north across a dead lake bed

The Red River of the North forms most of the North Dakota border and flows the wrong way, north into Manitoba and Lake Winnipeg. Its gradient is close to nothing, dropping only a few inches per mile in stretches, because it crosses the floor of Glacial Lake Agassiz, a meltwater lake that at its greatest extent held more water than all the modern Great Lakes together and covered this ground until roughly 8,000 years ago. The flat black soil of the Red River Valley is that lake bottom. The northward flow is also why Fargo and Moorhead flood in spring: the upstream end thaws first and sends water into a channel still locked in ice downstream.

Agassiz drained catastrophically to the southeast as well, through an outlet called Glacial River Warren that carved a valley up to five miles wide. The Minnesota River occupies it now and is far too small for the trench it runs in. Where the Minnesota joins the Mississippi below Fort Snelling, the meeting of a large valley and a smaller one is visible from the bluff.

Sixty below at Tower

The coldest reading ever taken in Minnesota was minus 60 F at Tower on 2 February 1996. The hottest was 114 F, recorded at Beardsley on 29 July 1917 and matched at Moorhead on 6 July 1936. A 174-degree spread puts Minnesota among the most extreme states in the country for temperature range, a consequence of sitting deep in a continental interior with no mountain barrier to the north and nothing between it and the Arctic. International Falls trades on this and holds a trademark on the Icebox of the Nation title. The state runs entirely on Central Time and covers 86,936 square miles, twelfth largest, bordering Wisconsin, Iowa, South Dakota and North Dakota plus the Canadian provinces of Ontario and Manitoba.

Common questions about Minnesota geography

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