Tri-state area

There are a number of areas in the 48 contiguous United States known informally as tri-state areas. A tri-state area is an area associated with a particular town or metropolis that lies across three states. Some, but not all, of these involve a state boundary tripoint.

The most frequently referenced tri-state area is that associated with the New York metropolitan area, which covers parts of the states of New York, New Jersey and Connecticut.

Three other prominent areas that have been labeled tri-state areas are the Cincinnati tri-state area, including Ohio, Kentucky, and Indiana; the Pittsburgh tri-state area, covering parts of Pennsylvania, Ohio, and West Virginia; and the Chicago tri-state area, also known as Chicagoland, which includes Illinois, Indiana, and Wisconsin.

Smaller tri-state areas include those of Dubuque, Iowa, which spills over into Illinois and Wisconsin; of Quincy, Illinois, which includes parts of Missouri and Iowa; Evansville, Indiana, which includes parts of Illinois and Kentucky; the Chattanooga, Tennessee tri-state area which includes Alabama and Georgia; and the Huntington (W.V.)-Ashland (Ky.)-Ironton (Oh.) Tri-State region, which incorporates areas of Kentucky, Ohio, and West Virginia. The Quincy, Evansville, and Huntington-Ashland areas are noteworthy for the states included all being separated by rivers.

The area that includes Washington, D.C. and the nearby parts of Maryland and the Virginias is sometimes loosely referred to as a "tri-state area," although the District of Columbia is not a state; however, with the presence of Jefferson County, West Virginia in the official Washington–Arlington–Alexandria Metropolitan Statistical Area, the region, as defined by the US Government, does in fact include three states. This area is more commonly/colloquially referred to as the "DMV" (DC, Maryland, Virginia).

The "Joplin District", a lead and zinc mining region of Oklahoma, Kansas and Missouri, produced mineral specimens known as "Tri-State" minerals, typically consisting mainly of sphalerite.

The term Tri-state area is used often in the children's television program Phineas and Ferb. The evil Dr. Doofenshmirtz makes reference in every episode to wanting to take over the tri-state area.

Land tripoints

NY-MA-CT Tripoint Marker

CT-RI-MA Tripoint Marker

The tripoint for Indiana, Michigan, and Ohio is marked with a brass disc located beneath a rural road that straddles Indiana's eastern border with the other two states.

Of the 62 points in the United States where three and only three states meet (each of which may be associated with its own tri-state area), 35 are on dry land. They are:

State 1	State 2	State 3	Notes
Alabama	Florida	Georgia	Marker on riverbank is actually a few feet above and west of true tripoint at high-water line.
Alabama	Georgia	Tennessee	Recently stolen marker on dry land at surface level and unmarked on lake in cavern directly below.
Arizona	Nevada	Utah	Marked.
Arkansas	Louisiana	Mississippi	Unmarked on silt island in river connected to west bank by riprap.
Arkansas	Louisiana	Texas	See Ark-La-Tex. Marker in process of being surrounded and absorbed by tree.
Arkansas	Missouri	Oklahoma	Marked.
Arkansas	Oklahoma	Texas	Unmarked on seasonal silt island or in river bed, but Oklahoma-Texas state line as revised in 2000 is defective in not extending from vegetation line on south bank to pre-established tripoint.
California	Nevada	Oregon	Marked.
Colorado	Kansas	Nebraska	Marked.
Colorado	Kansas	Oklahoma	8 Mile Corner. Marker is concealed in crypt beneath removable manhole cover.
Colorado	Nebraska	Wyoming	Marked.
Colorado	New Mexico	Oklahoma	Preston Monument
Colorado	Utah	Wyoming	Marked.
Connecticut	Massachusetts	New York	See Brace Mountain or Mount Frissell. Marked.
Connecticut	Massachusetts	Rhode Island	See Thompson, Connecticut. Marked.
Delaware	Maryland	Pennsylvania	See Delaware Wedge. Marked.
Georgia	North Carolina	Tennessee	Marked.
Idaho	Montana	Wyoming	Located within Yellowstone National Park. Marked.
Idaho	Nevada	Oregon	Marked.
Idaho	Nevada	Utah	Marked.
Idaho	Utah	Wyoming	Marked.
Indiana	Michigan	Ohio	Marker is located in a crypt beneath the surface of a rural road. Was set in 1999and used to have a removable metal plate protecting it, but it has been missing since fall 2010.
Iowa	Minnesota	South Dakota	True point is marked with a disc in the center of a T-shaped road intersection. A witness monument nearby in the South Dakota corner acknowledges the tri-point being set in 1859.
Kansas	Missouri	Oklahoma	Marked. On seldom used dead-end road. Apparently a teenagers' backwoods drinking spot.
Kentucky	Tennessee	Virginia	Tri-State Peak Located within Cumberland Gap National Historical Park. Marked.
Kentucky	Virginia	West Virginia	Marked.
Maryland	Pennsylvania	West Virginia	Marked.
Massachusetts	New Hampshire	Vermont	Marker is technically on dry land, but buried within river bed.
Massachusetts	New York	Vermont	Marked.
Montana	North Dakota	South Dakota	Marked.
Montana	South Dakota	Wyoming	Marked.
Nebraska	South Dakota	Wyoming	Marked.
New Jersey	New York	Pennsylvania	Marked by the Tri-State Monument in Port Jervis, New York by the confluence of the Delaware and Neversink Rivers.
New Mexico	Oklahoma	Texas	Texomex Marker
North Carolina	Tennessee	Virginia	Marked.

Water tripoints

Twenty-seven tripoints are under water:

State 1	State 2	State 3	Water	Notes
Alabama	Mississippi	Tennessee	Tennessee River
Arizona	California	Nevada	Colorado River
Arkansas	Mississippi	Tennessee	Mississippi River	Memphis, Tennessee metro area.
Arkansas	Missouri	Tennessee	Mississippi River
Connecticut	New York	Rhode Island	Long Island Sound	The part of New York that is in this tri-state area is Fishers Island. It is the New London, Connecticut metro area.
Delaware	New Jersey	Pennsylvania	Delaware River	Philadelphia metro area, at the east end of the Twelve-Mile Circle.
Georgia	North Carolina	South Carolina	Chatooga River	Located in river very near marker on dry land.
Idaho	Oregon	Washington	Snake River
Illinois	Indiana	Kentucky	Wabash River and Ohio River	Evansville, Indiana metro area. See Illinois–Indiana–Kentucky Tri-State Area.
Illinois	Indiana	Michigan	Lake Michigan	Known as either the Indiana Dunes or the Michigan Dunes Area
Illinois	Iowa	Wisconsin	Mississippi River	Dubuque, Iowa metro area.
Illinois	Kentucky	Missouri	Mississippi River and Ohio River	Little Egypt region popularly labeled as a tri-state area with St. Louis, Missouri, Carbondale, Illinois metro area, and Paducah, Kentucky being its nuclei.
Illinois	Michigan	Wisconsin	Lake Michigan
Indiana	Kentucky	Ohio	Ohio River	Cincinnati, Ohio metro area. The tripoint is near, but not precisely at, the confluence with the Great Miami River.
Iowa	Illinois	Missouri	Mississippi River and Des Moines River	Border with Lee County, Iowa
Iowa	Minnesota	Wisconsin	Mississippi River	La Crosse, Wisconsin metro area.
Iowa	Missouri	Nebraska	Missouri River
Iowa	Nebraska	South Dakota	Big Sioux River and Missouri River	Sioux City, Iowa metro area.
Kansas	Missouri	Nebraska	Missouri River
Kentucky	Missouri	Tennessee	Mississippi River	Three separate tripoints, due to meanders of the river (though probably only a single tri-state area surrounding them all). See also Kentucky Bend.
Kentucky	Ohio	West Virginia	Big Sandy River and Ohio River	Huntington (W.V.)-Ashland (Ky.)-Ironton (Oh.) Tri-State region.
Maryland	Virginia	West Virginia	Potomac River	Unmarked, at low water line, and almost always submerged.
Michigan	Minnesota	Wisconsin	Lake Superior
Minnesota	North Dakota	South Dakota	Bois de Sioux River	Not directly marked and most probably within river.
Ohio	Pennsylvania	West Virginia	Ohio River	Technically the Beginning Point of the U.S. Public Land Survey, although the actual monument is 1,112 feet north of the tripoint due to the tripoint's current location under water; Pittsburgh Tri-State.

Regions with no Tripoint

The following tri-state areas are also notable, but have no tripoint:

State 1	State 2	State 3	Notes
Alabama	Florida	Mississippi	The Gulf Coast region.
Connecticut	New Jersey	New York	New York metropolitan area. See New York Metropolitan Area.
Delaware	Maryland	New Jersey	Wilmington, DE metropolitan area
Delaware	Maryland	Virginia	Delmarva Peninsula
Idaho	Montana	Washington	Spokane, WA area; connected by Interstate 90
Illinois	Indiana	Wisconsin	Chicago metro area
Kansas	Oklahoma	Texas	The Liberal, Kansas area has a close relationship with the Oklahoma and Texas panhandles.
Massachusetts	Maine	New Hampshire	The Boston to Portland metro area; though the two are separated by New Hampshire, Maine was actually part of Massachusetts before becoming a separate state in 1820.
New York	Pennsylvania	Ohio	Erie metropolitan area, a.k.a. North Coast and Niagara Frontier. Shares two tripoints with Ontario (PA-ON-OH and PA-ON-NY), both within Lake Erie.
South Carolina	North Carolina	Tennessee	The Spartanburg, South Carolina, Asheville, North Carolina, Johnson City, Tennessee, and Kingsport, Tennessee metro areas along Interstate 26
Vermont	Maine	New Hampshire	Northern New England
West Virginia	Virginia	North Carolina	Important section of Interstate 77 connecting Charleston, West Virginia with Charlotte, North Carolina; passes through Wytheville, Virginia

See also

• Four Corners
• Four State Area
• Phineas and Ferb (the series' setting in an undefined tri-state area is mentioned in every episode)
• Twin cities (geographical proximity), which includes tri-city

External links

• Tripoint Guide
• The US Tri-Corner Home Page