A physical map of Michigan can be read as four regions: the rugged, ore-rich Superior Upland of the western Upper Peninsula; the flat, swampy lowlands of the eastern Upper Peninsula; the hilly, forested Northern Lower Peninsula around Cadillac; and the level farm and city country of the Southern Lower Peninsula, from Saginaw Bay to the Detroit River. Michigan covers 250,490 km² (96,716 sq mi) including its Great Lakes waters, about 42% of which is water, and it has 5,292 km (3,288 mi) of shoreline, the longest freshwater coast of any US state. The highest ground is in the Huron Mountains, where Mount Arvon and Mount Curwood both stand at about 603 m (1,979 ft); a 2025 resurvey put Curwood ahead by 12 cm. The lowest point is the Lake Erie shore at 174 m (571 ft). The largest inland lake is Houghton Lake (81 km²) and the longest river is the Grand, at 406 km (252 mi).
Those four regions sit on two very different foundations. The western Upper Peninsula is the southern edge of the Canadian Shield, ancient volcanic and metamorphic rock that pokes through the soil. Everything else rests on the Michigan Basin, a bowl of sedimentary layers that dip toward a centre in Gladwin County, where the Precambrian basement lies about 4,900 m (16,000 ft) down. Ice sheets then scraped and buried both, leaving the moraines, sands and 11,037 inland lakes on today's map.
The Superior Upland: Huron Mountains, Porcupine Mountains and the Keweenaw
The Upper Peninsula holds 42,420 km² (16,378 sq mi) of land, 29% of the state, and its western half is the only part of Michigan that looks like hill country. This is the Superior Upland, the worn-down stumps of far older ranges.
The Huron Mountains, in Marquette and Baraga counties above Lake Superior, carry the state's top two peaks just a few kilometres apart in L'Anse Township. Mount Curwood was long listed as the high point until a 1982 survey made Mount Arvon one foot taller; then 2025 surveys of both peaks reversed the result, putting Curwood 0.4 ft (12 cm) higher. Both round to 603 m. A man-made rival complicates things further: in 2018 the National Oceanic and Atmospheric Administration reported that the top of the Tilden Mine waste pile near Ishpeming stood slightly above 610 m (2,000 ft).
That mine works the Marquette Iron Range around Ishpeming and Negaunee, found in 1844 when William A. Burt's survey compasses went haywire and mined continuously since 1847.
Further west, in Ontonagon and Gogebic counties, the Porcupine Mountains form a long basalt and conglomerate escarpment parallel to the Lake Superior shore. Behind the escarpment sits Lake of the Clouds, and on the inland ridge beyond it is Summit Peak, 595 m (1,958 ft). The range shelters at least 13,000 ha (31,000 acres) of old-growth northern hardwood forest, the largest such stand in North America west of the Adirondacks. Nearby lies Lake Gogebic, the Upper Peninsula's largest natural lake.
The Keweenaw Peninsula juts about 105 km (65 mi) northeast into Lake Superior and is cut by the Keweenaw Waterway at Houghton and Hancock. Its lava flows erupted between 1.096 and 1.087 billion years ago in the Midcontinent Rift and left the only rocks on Earth where large-scale deposits of nearly pure native copper could be mined. Mining ran from the 1840s to the 1960s.
Isle Royale, the outlier of this region, lies 90 km (56 mi) off the Keweenaw and only about 24 km (15 mi) from Ontario. It covers 535 km² (207 sq mi), the largest natural island in Lake Superior, and rises to 425 m (1,394 ft) at Mount Desor. It became a national park in 1940.
Eastern Upper Peninsula Lowlands: Pictured Rocks, Seney and Tahquamenon
East of Marquette the Shield rocks give way to flat-lying sandstone and limestone, and the land flattens. Bedrock still meets the lake in places, most dramatically at Pictured Rocks National Lakeshore in Alger County, which runs 68 km (42 mi) between Munising and Grand Marais. Its name comes from more than 20 km of mineral-stained sandstone cliffs northeast of Munising that stand up to 60 m (200 ft) above Lake Superior, carved into caves, arches and turret-like stacks. Congress made it the first national lakeshore in the United States in 1966.
Inland, the drainage is so poor that much of the region is bog and swamp. The Seney National Wildlife Refuge in Schoolcraft County protects 385 km² (95,212 acres) of managed wetland, including the Strangmoor Bog, the best surviving sub-arctic patterned bog in the lower 48 states.
Water draining those cedar swamps picks up tannins, which is why the Tahquamenon River runs the colour of tea. Shortly before it reaches Whitefish Bay it drops over the Upper Tahquamenon Falls, a single plunge of about 15 m (48 ft) across a river more than 60 m (200 ft) wide. In spring runoff as much as 190,000 litres (50,000 US gal) a second pour over, making it the third most voluminous waterfall east of the Mississippi after Niagara and Cohoes.
The peninsula's southern rim is the Niagara Escarpment, the same arc of Silurian limestone and dolomite that Niagara Falls spills over on the US–Canada border. It enters Michigan from the islands of northern Lake Huron, south of Sault Ste. Marie, and runs west down the Garden Peninsula toward Wisconsin. Off its eastern end lies Drummond Island, which at 350 km² (134 sq mi) is the seventh-largest lake island in the world. At the region's eastern tip, the St. Marys River drops 6.4 m (21 ft) from Lake Superior toward Lake Huron at Sault Ste. Marie. The Soo Locks, opened in 1855, lift about 10,000 ships a year past the rapids.
The Straits of Mackinac and Michigan's Island Chains
The two peninsulas almost touch at the Straits of Mackinac, where Lake Michigan joins Lake Huron. Until 1 November 1957, the only link was by ferry. That day the Mackinac Bridge opened between St. Ignace and Mackinaw City, carrying Interstate 75 for 8.038 km (26,372 ft); it remains the longest suspension bridge between anchorages in the Western Hemisphere. Michigan received the western three-quarters of the Upper Peninsula in the 1836 settlement of the Toledo War with Ohio, and the result is a state so stretched that Ironwood, at the western tip, lies 1,010 km (630 mi) by road from Lambertville in the southeastern corner.
Mackinac Island sits at the eastern end of the straits, a limestone island of 11.3 km² (4.35 sq mi) whose Odawa name, Michilimackinac, is usually translated "Great Turtle". With Bois Blanc and Round islands, it belongs to Mackinac County. Westward lie the Beaver and Fox island groups in Lake Michigan. Michigan has about 150 lighthouses, more than any other state, the first built between 1818 and 1822.
Northern Lower Peninsula: Cadillac Highlands, Houghton Lake and the Au Sable
South of the bridge, the 21 counties of Northern Michigan, home to 506,658 people in 2020, form the Lower Peninsula's high country. The surface here is mostly glacial: conical hills and moraines rarely more than a few hundred feet high, with broad sandy outwash plains between them. The highest ground is around Cadillac, where Briar Hill reaches 520 m (1,705 ft), though surveys have not settled whether it or one of several nearby points is the true high point of the Lower Peninsula.
A low north-south water divide splits the peninsula, with the larger western side sloping toward Lake Michigan. The sandy uplands also hold the state's largest inland lakes. Houghton Lake in Roscommon County is about 16 km (10 mi) long and covers 81 km² (20,044 acres); it receives water from spring-fed Higgins Lake through the Cut River and is the source of the Muskegon River. Flowing east, the Au Sable River runs 222 km (138 mi) to Lake Huron at Oscoda and is a designated blue-ribbon trout stream.
The Lake Michigan Dune Coast: Sleeping Bear to Grand Haven
Prevailing westerly winds blowing across Lake Michigan have built sandy beaches and dunes along much of the eastern shore, the largest freshwater dune system in the world. The region begins at the Leelanau Peninsula, the mitten's "little finger", and Grand Traverse Bay. Sleeping Bear Dunes National Lakeshore, created on 21 October 1970, protects 288 km² (71,199 acres) along 56 km (35 mi) of coast in Benzie and Leelanau counties, plus the two Manitou islands. Its high bluffs are perched dunes: a thin layer of wind-blown sand resting on a thick deposit of glacial debris left by the Wisconsin glaciation 10,000 to 14,000 years ago.
Southward, the major rivers of western Michigan cut through the dune belt to reach the lake: the Manistee, the Muskegon, the Grand and the Kalamazoo, then the St. Joseph near the Indiana line. The Grand is the longest river in the state. It rises from springs in Hillsdale County, flows through Jackson, Lansing, Ionia and Grand Rapids, and enters Lake Michigan at Grand Haven, falling from about 384 m (1,260 ft) to 176 m (577 ft) along its 406 km (252 mi). For a lake-by-lake view of this shore, see our Lake Michigan geography guide.
Southern Lower Peninsula: Saginaw Bay, the Thumb and the Detroit River
The southern half of the mitten is the flattest, most farmed and most urban part of Michigan. The surface is generally level, broken only by low moraines and conical glacial hills. The peninsula measures 446 km (277 mi) north to south and 314 km (195 mi) east to west, and even its most inland point, near Lansing, is no more than 137 km (85 mi) from a Great Lake.
On the east side, the Thumb projects into Lake Huron and encloses Saginaw Bay, 2,960 km² (1,143 sq mi) of shallow water. The bay's watershed is the largest drainage basin in Michigan, about 15% of the state's land, and holds the largest contiguous freshwater coastal wetland system in the United States. The flat, fertile Thumb grows sugar beets and navy beans.
The southeastern corner is a chain of water rather than land. Lake Huron empties through the St. Clair River into Lake St. Clair, about 1,100 km² in area yet only 3.4 m (11 ft) deep on average, then down the Detroit River, 44 km (28 mi) long, past Detroit and Windsor into Lake Erie. Here, on the Lake Erie shore near Monroe, is the state's lowest point at 174 m (571 ft).
Almost every part of Michigan's map drains to the Great Lakes, and no point in the state is more than 9.7 km (6 mi) from a natural body of water. To see how those 11,000-plus inland lakes rank by size, read our guide to the largest lakes in Michigan, or step back to the whole system with what the Great Lakes are and how they formed.