U S Roads --- Idaho

IDAHO HIGHWAY HISTORY

Information on Idaho's historic highways and highway system

SAMPSON TRAILS IN IDAHO

One of Idaho's very first highway systems was a network of trails known as Sampson trails. Sampson trails were proposed by and named after Charles Sampson. Charles Sampson was a Boise businessman who also was a proponent of good road networks. His system of roads used a single letter designation "A, B, C, D, ..." and the Trails were marked marked with a bold black letter on an orange paint background. These routes were replaces by the more modern numbered state highway system and fell out of use in the 1930's.

Historic Sampson Trails
	Route Description	Replaced By
A	Boise to Wyoming via Twin Falls, Pocatello	US 30, US 30N
B	Boise to Canada via Lewiston, Coeur d'Alene	US 30, US 30N, US 95, SH 1
C	Pocatello to Montana via Idaho Falls	US 91, US 191, US 20
D	Boise to New Meadows via Banks	became SH 15 then SH 55
E	Designation Uncertain
F	Boise to Blackfoot via Stanley	SH 21, SH 17, US 93, SH 27
G	Mountain Home to Picabo via Fairfield	SH 22
H	Bliss to Trude via Arco	SH 24, SH 23, SH 22, SH 29, an unnumbered road
I	Pioneer to Idaho Falls	became an unnumbered road
J	Nevada to Shoshone via Twin Falls	US 93
K	Utah to McCammon via Preston	US 91
L	Designation Uncertain
M	Washington to Montana via Coeur d'Alene	became US 10 then I-90
N	Bonners Ferry to Montana	US 2
O	Oregon to Caldwell	SH 49, SH 18
P	Utah to Downey	SH 36
Q	Declo to Fairfield	SH-25, SH-46
R	Designation Uncertain
S	Oregon to Nampa	SH-45, an unnumbered road
T	Star to Grimes Pass	SH-16, unnumbered road, SH-17
U	Utah to Montpelier	SH 35
V	Utah to Montpelier	US 89
W	Designation Uncertain
X	Designation Uncertain
Y	Bonners Ferry to Canada	US 95
Z	Designation Uncertain