I-90 is the longest
Interstate Highway in the United States, spanning across the northern portion of the coterminous part of the country. From the
Wisconsin–
Illinois state line to
Massachusetts, approximately of I-90 uses
turnpikes and other tolled highways with the exception of segments in
Chicago, northeastern Ohio,
Pennsylvania, and
Albany, New York. The toll road sections comprise 25 percent of the freeway's total length. According to 2011 data from the
Federal Highway Administration, the busiest section of I-90 is in the Chicago area, where a
daily average of 306,574 vehicles use the freeway. The lowest daily traffic counts on I-90 were recorded in Wyoming, where an average of 9,820 vehicles used rural sections of the freeway.
Washington |alt=Aerial view of a divided highway making two turns in a densely forested area. The western terminus of I-90 is at an intersection with
Washington State Route 519 and 4th Avenue South in the
SoDo neighborhood of
Seattle. The junction is south of
Downtown Seattle, adjacent to the
Port of Seattle and two major sports stadiums,
Lumen Field and
T-Mobile Park. The freeway travels east through an interchange with
I-5 and around
Beacon Hill before it enters the
Mount Baker Ridge Tunnel alongside the
2 Line of the
Link light rail system. I-90 emerges from the tunnel on a pair of
floating bridges, among the longest of their kind: the eastbound-only
Lacey V. Murrow Memorial Bridge and the
Homer M. Hadley Memorial Bridge, which carries westbound traffic and the light rail tracks. The floating bridges cross
Lake Washington to
Mercer Island, where I-90 travels through a series of tunnels under of parkland, including
Aubrey Davis Park. The freeway continues from the island and enters
Bellevue, the largest city of the
Eastside region, and intersects
I-405 near
Factoria. I-90 then travels along
Lake Sammamish and through
Issaquah as it leaves the Seattle metropolitan area and ascends into the
Cascade Range on the
Mountains to Sound Greenway, a designated
National Heritage Area and
National Scenic Byway. The freeway crosses
Snoqualmie Pass, elevation , at the crest of the mountain range near a
ski resort. From Snoqualmie Pass, I-90 follows the
Yakima River into the
Kittitas Valley and intersects
I-82 in
Ellensburg after a brief
concurrency with
U.S. Route 97 (US 97). The highway crosses the
Columbia River on the
Vantage Bridge and turns northeast to climb the cliffs of the
Columbia Plateau near
George. After traveling east across
Moses Lake and the surrounding agricultural region, I-90 begins a long concurrency with
US 395 at
Ritzville as the highways turn northeast towards
Spokane. I-90/US 395 is joined by
US 2 through western Spokane, where it intersects
US 195. The freeway crosses downtown Spokane on an elevated viaduct and splits from US 2 and US 395 to continue east across
Spokane Valley towards the Idaho state line. I-90 then turns southeast to bypass Coeur d'Alene and travel along a series of ridges that face
Lake Coeur d'Alene, crossing an arm of the lake on the
Veterans Memorial Centennial Bridge. The freeway continues east across
Fourth of July Summit and descends into the Silver Valley, where it follows the
Coeur d'Alene River through several small towns along the historic
Mullan Road. I-90 serves the cities of
Kellogg and
Wallace before it ascends into the
Bitterroot Range and crosses
Lookout Pass, which also marks the Montana state line. It descends from Lookout Pass along the
St. Regis and
Clark Fork rivers between the foothills of the Bitteroot Range and
Coeur d'Alene Mountains. The freeway travels east through the
Alberton Gorge and crosses the Clark Fork River several times before it reaches the head of the
Missoula Valley. After a short concurrency with
US 93, I-90 runs along the north side of
Missoula and joins
US 12 to continue southeast along the foothills of the
Garnet Range and
Sapphire Mountains. The freeway travels east across the
Jefferson Valley and passes the headwaters of the
Missouri River near
Three Forks. It then enters the
Gallatin Valley. I-90 travels around
Bozeman, where it is joined by
US 191, and crosses
Bozeman Pass between the
Bridger and
Gallatin mountains. At the east end of the mountains, the freeway begins to follow the
Yellowstone River and is briefly concurrent with
US 89, which serves
Yellowstone National Park, and splits from US 191 at
Big Timber. I-90 continues along the Yellowstone River through
Billings, overlapping with
US 87 and
US 212, until it reaches
Lockwood, the western terminus of
I-94. The freeways split and I-90 continues east across the
Bighorn Basin before it turns south near
Hardin to follow the
Little Bighorn River into the
Crow Indian Reservation. The highway passes
the site of the
Battle of the Little Bighorn near
Crow Agency and continues south along the river and the
Wolf Mountains into Wyoming. From 1995 to 1999, there was no numbered daytime
speed limit on rural highways in Montana, including I-90. The speed limit was simply defined as "reasonable and proper" as determined on a case-by-case basis by the
Montana Highway Patrol until the
Montana Supreme Court ruled it was unconstitutional. The maximum daytime speed limit in Montana was initially set at in 1999 and was later raised to in 2015.
Wyoming , from I-90|alt=A multi-story building named the "Mill Inn" and tall grain elevator, seen from an elevated vantage point I-90 serves a portion of northeastern Wyoming that is primarily rural. The freeway, briefly concurrent to
US 14, travels southeast along a series of creeks to
Sheridan in the northeastern foothills of the
Bighorn Mountains. I-90 and US 87 split in Sheridan and travel parallel to each other to
Fort Phil Kearny, where they rejoin and continue south past
Lake Desmet to
Buffalo. The highways split again near Buffalo at a junction with
I-25, which overlaps with US 87 to
Casper. From Buffalo, the highway turns east to cross the
Powder River Basin, a region with several large coal mines. I-90 then reaches
Gillette, where it begins a concurrency with US 14 and
US 16 to a three-way split in
Moorcroft. The freeway continues into the
Bear Lodge Mountains (part of the
Black Hills) and is rejoined in
Sundance by US 14, which looped north to serve the
Devils Tower. I-90/US 14 then continues northeast to
Beulah, where it enters
South Dakota. It then skirts the northern edge of Rapid City, which is served by spur route
I-190, and passes
Ellsworth Air Force Base while it continues east across the plains. I-90 splits from US 14 near
Wall, home to the
Wall Drug roadside attraction and located northeast of
Badlands National Park. The freeway travels southeast into the
Buffalo Gap National Grassland and also passes a pair of decommissioned
missile silos that form the
Minuteman Missile National Historic Site. I-90 continues east along the top of a plateau that faces the
White River and passes near
Kadoka and
Murdo.
US 83 briefly joins the highway from Murdo to
Vivian, where it splits off to serve the state capital of
Pierre. From Chamberlain, I-90 continues east across the plains and past several small towns near the city of
Mitchell. It then reaches the
Sioux Falls area, where it bypasses the city to the north and intersects
I-29 and
I-229. I-90 leaves Sioux Falls and crosses into
Minnesota near
Brandon. From the South Dakota border near
Beaver Creek to
Albert Lea, the freeway travels east across farmland and towns in the plains and rolling hills of the
Buffalo Ridge. It also intersects several north–south highways, including
US 75 in
Luverne,
US 59 in
Worthington,
US 71 in
Jackson, and
US 169 in
Blue Earth. I-90 travels around the northern outskirts of Albert Lea and intersects
I-35 northeast of the city. It then reaches
Austin and a brief concurrency with
US 218. From Austin, the freeway turns northeast to head towards
Rochester, which it bypasses to the south and intersects
US 63 and
US 52. I-90 continues east into the hilly
Driftless Area and descends from the bluffs that overlook
Lake Onalaska on the
Mississippi River. It turns southeast at
Dakota and is joined by US 14 until the highways split near
La Crescent. I-90 turns east before it reaches La Crescent, where it crosses the Mississippi River on the
Dresbach Bridge into Wisconsin.
Wisconsin bridge near
La Crosse I-90 enters Wisconsin near
La Crosse and bisects
French Island before it reaches
Onalaska. This section is briefly concurrent to
US 53 between La Crosse and Onalaska. The freeway travels east, generally along the
La Crosse River, through several towns and
Fort McCoy before it reaches a junction with I-94 in
Tomah. The two Interstates join at Tomah and travel southeast along the edge of the hills of the
Western Upland, following the
Lemonweir and
Wisconsin rivers. It passes
Wisconsin Dells, situated on the
gorge of the same name and home to several
water parks and
theme parks. The freeway travels east from Wisconsin Dells to the
Portage area, where
I-39 begins its concurrency with I-90/I-94. The highway then crosses the Wisconsin River and travels south towards
Madison, where it forms an eastern bypass of the city. East of Madison, I-94 separates from I-39/I-90, which continues southeast through
Edgerton and
Janesville. The highway turns south and enters
Beloit, where it intersects
I-43 and crosses into
Illinois. The tollway cuts through the northwestern suburbs of Chicago, where it intersects
I-290 in
Schaumburg and passes the north side of
O'Hare International Airport. On the east side of the airport in
Rosemont, I-90 intersects
I-294 and
I-190, the latter of which serves the airport's passenger terminals and marks the end of the tollway. I-90 turns southeast and is rejoined by I-94 in
Irving Park, where it gains a set of
reversible express lanes that travel for toward the
Near West Side. The Kennedy Expressway travels south through the Near West Side, opposite the
Chicago River from the
Chicago Loop (the city's central business district), and intersects I-290 again at the
Jane Byrne Interchange. The freeway continues onto the
Dan Ryan Expressway and crosses the Chicago River near
Chinatown and an interchange with
I-55. The Dan Ryan is the widest section of I-90, at 12 through lanes, and is split between
local and express lanes. I-90/I-94 is joined by the
"L" Red Line in the median of the expressway through the city's
South Side, I-90 splits from the Dan Ryan Expressway in
Englewood and turns southeast onto the tolled
Chicago Skyway. The tolled Skyway travels towards the Indiana state line, which the freeway crosses near the
Calumet River in the
East Side. From the Illinois state line, the tollway travels south through
Hammond and turns east to follow the
Grand Calumet River through northern
Gary, where it intersects
US 41 and US 12. I-90 then crosses
I-65 in eastern Gary and I-94 in
Lake Station, where it begins a concurrency with I-80. The turnpike travels southeast through a rural area near the southwest shore of
Lake Erie, where it passes the cities of
Fremont and
Sandusky. Near Norwalk, the highway turns northeast to follow
State Route 2 (SR 2) and heads to
Elyria, where I-90 splits from I-80 (which remains on the turnpike). The freeway then merges with SR 2 and continues northeast through the lakeshore suburbs west of
Cleveland, including
Rocky River and
Lakewood. I-90 and SR 2 separate after crossing the
Rocky River and travel parallel to each other as they enter Cleveland. I-90 continues through the southwestern residential neighborhoods of Cleveland and reaches a junction with
I-71 and
I-490 in
Tremont, where it turns north. The Innerbelt skirts the south side of Downtown Cleveland, where it intersects
I-77 near
Progressive Field and turns north to bisect the
Goodrich–Kirtland Park neighborhood.) and rejoins SR 2 on the
Cleveland Memorial Shoreway until they split again in
Euclid. I-90 briefly turns southeast but resumes its northeastern route after a junction with
I-271 in
Willoughby Hills. The freeway travels parallel to the Lake Erie shoreline through farmland and exurban towns and crosses into Pennsylvania near
Conneaut. It enters the state in
Springfield Township and passes through rural areas along the lake shore, parallel to US 20 and the
Lake Road. The freeway then travels through the southern outskirts of
Erie, where it intersects
I-79 and
US 19. I-90 returns to the rural areas of northeastern Erie County and intersects
I-86 before it reaches the New York state line near the borough of
North East. At a junction with I-290 near
Buffalo Niagara International Airport, I-90 turns east to follow the historic
Water Level Route of the
New York Central Railroad, itself parallel to the 19th-century
Erie Canal. The Thruway passes south of
Rochester, which it serves via a loop on
I-490 and the direct north–south spur
I-390. I-90 travels through the
Finger Lakes region and moves closer to the Erie Canal as it approaches the
Syracuse area. It travels through the city's northern outskirts, where it intersects
I-690,
I-81, and
I-481 from west to east. It then continues to
Utica, where the Thruway runs along the north side of the
Mohawk River (part of the Erie Canal). as a result, the mileposts and exit numbers on I-90 through most of New York run backwards compared to the federal preference for mile-based numbers increasing from west to east. The Berkshire Connector uses west-to-east mileposts and exit numbers with a "B" prefix;
Massachusetts in Boston's
Fenway–Kenmore neighborhood, seen from the
Prudential Tower.
Fenway Park is visible at top left.|alt=Aerial view of a divided highway in a dense urban neighborhood, passing under several bridges and near multi-story buildings and a baseball stadium I-90 in Massachusetts is concurrent with the entirety of the
Massachusetts Turnpike (also known as "the Pike" or "MassPike"). The turnpike begins at the New York state line in
West Stockbridge and travels southeast through the
Berkshires to the
Pioneer Valley. The highway travels through the northern suburbs of
Springfield, where it intersects
I-91 and crosses the
Connecticut River into
Chicopee. I-90 then crosses over
I-391 without an interchange and serves as the northern terminus of
I-291 on the eastern outskirts of the city. The turnpike continues east through the hills of
Central Massachusetts and serves as the eastern terminus of
I-84 in the town of
Sturbridge. I-90 intersects
I-93 on the south side of
Downtown Boston and travels under the
Fort Point Channel to serve the
Seaport District. The turnpike then enters the
Ted Williams Tunnel, which travels northeast under
Boston Harbor to the passenger terminals at
Logan International Airport. After it passes the northwest side of the airport, I-90 terminates at an interchange with
Route 1A in
East Boston. ==History==