The
Idaho Transportation Department (ITD) is responsible for the establishment and classification of a state highway network, including of roads that are classified as
Interstate Highways
The Dwight D. Eisenhower National System of Interstate and Defense Highways, commonly known as the Interstate Highway System, is a network of controlled-access highways that forms part of the National Highway System in the United States. Th ...
,
U.S. Highways
The United States Numbered Highway System (often called U.S. Routes or U.S. Highways) is an integrated network of roads and highways numbered within a nationwide grid in the contiguous United States. As the designation and numbering of these hi ...
, and
state highways
A state highway, state road, or state route (and the equivalent provincial highway, provincial road, or provincial route) is usually a road that is either ''numbered'' or ''maintained'' by a sub-national state or province. A road numbered by a ...
within the state of
Idaho
Idaho ( ) is a state in the Pacific Northwest region of the Western United States. To the north, it shares a small portion of the Canada–United States border with the province of British Columbia. It borders the states of Montana and Wyomi ...
in the
United States. The current state highway marker consists of a white background, black numbering, and a solid black geographic outline of the state of Idaho.
History
During the 1920s, in lieu of numbering its highways, Idaho had a system of lettered Sampson Trails.
Rand McNally
Rand McNally is an American technology and publishing company that provides mapping, software and hardware for consumer electronics, commercial transportation and education markets. The company is headquartered in Chicago, with a distribution ...
Auto Road Atlas, 1926, accessed via th
Broer Map Library
/ref> They were marked by businessman Charles B. Sampson of Boise
Boise (, , ) is the capital and most populous city of the U.S. state of Idaho and is the county seat of Ada County. On the Boise River in southwestern Idaho, it is east of the Oregon border and north of the Nevada border. The downtown area' ...
at no expense to the state, using orange-colored shields.[Senate Concurrent Resolution No. 8, "a concurrent resolution...to permit Charles B. Sampson to extend the marking system of the Sampson Trail..." passed February 16, 1933] By 1929, the trails system had included of marked highways that covered most of the state. By the mid-1930s, the state had adopted a more standard system of numbered state highways.
In 1978, the ITD began using brown state highway markers to denote scenic
Scenic may refer to:
* Scenic design
* Scenic painting
* Scenic overlook
* Scenic railroad (disambiguation)
* Scenic route
* Scenic, South Dakota, United States
* Scenic (horse), a Thoroughbred racehorse
Aviation
*Airwave Scenic, an Austrian p ...
Idaho highways, in addition to the main highway markers that featured a black background and white lettering and the name "IDAHO" in black lettering inside a white geographic outline of the state. The brown markers were discontinued around 2012, and in April 2020, ITD changed the coloring of the main state highway marker to its current color scheme, also adding a wide version of the marker for three-digit highways and removing the word "IDAHO" from all markers in the process.
Sampson Trails
The following Sampson Trails were marked:
* A, Boise
Boise (, , ) is the capital and most populous city of the U.S. state of Idaho and is the county seat of Ada County. On the Boise River in southwestern Idaho, it is east of the Oregon border and north of the Nevada border. The downtown area' ...
to Wyoming via Twin Falls and Pocatello
Pocatello () is the county seat of and largest city in Bannock County, with a small portion on the Fort Hall Indian Reservation in neighboring Power County, in the southeastern part of the U.S. state of Idaho. It is the principal city of the ...
; became US-30 and US-30N
* B, Boise
Boise (, , ) is the capital and most populous city of the U.S. state of Idaho and is the county seat of Ada County. On the Boise River in southwestern Idaho, it is east of the Oregon border and north of the Nevada border. The downtown area' ...
to Canada via Lewiston and Coeur d'Alene; became US-30, US-30N, US-95, and SH-1
* C, Pocatello
Pocatello () is the county seat of and largest city in Bannock County, with a small portion on the Fort Hall Indian Reservation in neighboring Power County, in the southeastern part of the U.S. state of Idaho. It is the principal city of the ...
to Montana via Idaho Falls
Idaho Falls ( Shoshoni: Dembimbosaage) is a city in and the county seat of Bonneville County, Idaho, United States. It is the state's largest city outside the Boise metropolitan area. As of the 2020 census, the population of Idaho Falls was 6 ...
; became US-91 and US-191
* D, Boise
Boise (, , ) is the capital and most populous city of the U.S. state of Idaho and is the county seat of Ada County. On the Boise River in southwestern Idaho, it is east of the Oregon border and north of the Nevada border. The downtown area' ...
to New Meadows via Banks
A bank is a financial institution that accepts deposits from the public and creates a demand deposit while simultaneously making loans. Lending activities can be directly performed by the bank or indirectly through capital markets.
Because ...
; became SH-15 (today's SH-55)
* E, not on the 1926 map
* F, Boise
Boise (, , ) is the capital and most populous city of the U.S. state of Idaho and is the county seat of Ada County. On the Boise River in southwestern Idaho, it is east of the Oregon border and north of the Nevada border. The downtown area' ...
to Blackfoot
The Blackfoot Confederacy, ''Niitsitapi'' or ''Siksikaitsitapi'' (ᖹᐟᒧᐧᒣᑯ, meaning "the people" or " Blackfoot-speaking real people"), is a historic collective name for linguistically related groups that make up the Blackfoot or Bla ...
via Stanley; became SH-21, SH-17, US-93 (today's SH-75), and SH-27
* G, Mountain Home to Picabo via Fairfield; became SH-22 (today's US-20)
* H, Bliss
BLISS is a system programming language developed at Carnegie Mellon University (CMU) by W. A. Wulf, D. B. Russell, and A. N. Habermann around 1970. It was perhaps the best known system language until C debuted a few years later. Since then, C b ...
to Trude via Arco
ARCO ( ) is a brand of gasoline stations currently owned by Marathon Petroleum after BP sold its rights. BP commercializes the brand in Northern California, Oregon and Washington, while Marathon has rights for the rest of the United States and ...
; became SH-24, SH-23, SH-22, SH-29, and an unnumbered road (today's US-20 and US-26)
* I, Pioneer to Idaho Falls
Idaho Falls ( Shoshoni: Dembimbosaage) is a city in and the county seat of Bonneville County, Idaho, United States. It is the state's largest city outside the Boise metropolitan area. As of the 2020 census, the population of Idaho Falls was 6 ...
; became an unnumbered road
* J, Nevada to Shoshone via Twin Falls; became US-93
* K, Utah to McCammon via Preston
Preston is a place name, surname and given name that may refer to:
Places
England
*Preston, Lancashire, an urban settlement
**The City of Preston, Lancashire, a borough and non-metropolitan district which contains the settlement
**County Boro ...
; became US-91
* L, not on the 1926 map
* M, Washington
Washington commonly refers to:
* Washington (state), United States
* Washington, D.C., the capital of the United States
** A metonym for the federal government of the United States
** Washington metropolitan area, the metropolitan area centered o ...
to Montana via Coeur d'Alene; became US-10
* N, Bonners Ferry to Montana; became US-2
* O, Oregon to Caldwell
Caldwell may refer to:
People
* Caldwell (surname)
* Caldwell (given name)
* Caldwell First Nation, a federally recognized Indian band in southern Ontario, Canada
Places
Great Britain
* Caldwell, Derbyshire, a hamlet
* Caldwell, Eas ...
; became SH-49 and SH-18
* P, Utah to Downey Downey may refer to:
People
* Downey (surname)
*Robert Downey Jr.
Places
*Downey, California, US
* Downey, Idaho, US
* Downey, Iowa, US
Businesses
* W. & D. Downey, photographic studio
* Downey Studios, created out of a former Boeing plant
Scho ...
; became SH-36
* Q, Declo to Fairfield; became SH-25 and SH-46
* R, not on the 1926 map
* S, Oregon to Nampa; became unnumbered road and SH-45
* T, Star
A star is an astronomical object comprising a luminous spheroid of plasma held together by its gravity. The nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night, but their immense distances from Earth ma ...
to Grimes Pass; became SH-16, unnumbered road, and SH-17
* U, Utah to Montpelier; became SH-35
* V, Hailey to Stanley; became US-93 (today's SH-75)
* W, not on the 1926 map
* X, not on the 1926 map
* Y, Bonners Ferry to Canada; became US-95
State highways
See also
* List of Interstate Highways in Idaho
* List of U.S. Highways in Idaho
References
External links
Idaho Transportation Department
(archived April 27, 2004)
Pend Oreille Scenic Byway
{{DEFAULTSORT:List of Idaho State Highways
State Highways
A state highway, state road, or state route (and the equivalent provincial highway, provincial road, or provincial route) is usually a road that is either ''numbered'' or ''maintained'' by a sub-national state or province. A road numbered by a ...