AARoads:United States/Idaho/highway names

Most information is from the meeting minutes and 1923 and 1925 maps (the latter bolded below).

• Alexander-Lund-Bancroft Road
• Ammon Spur: Idaho Falls to Ammon, removed 1953
• Arrow-Deary-Harvard Highway? SH-42: Spalding to Harvard
• Ashton-Drummond-Tetonia Road SH-32
• 32 Bannock Highway SH-38: Holbrook to Pocatello
• 36 Bear Lake Highway SH-35: Utah to Montpelier
• Beeches Corner South Road
• Bellevue-Gannett Highway
• Boise-Stanley Highway SH-21: Boise to Stanley
  • Former 1 Arrowrock Highway: Boise to Arrowrock
  • Former 35 Forest Highway: Lowman? to Stanley
• Boise Valley Highway: included Desert Junction-Middleton
• Bruneau-Duck Valley Highway
• Buhl-Castleford Highway SH-73: included Buhl southwest
• Canyon Highway SH-4: Wallace to Montana
• 3 Camas Prairie Highway? SH-13: Grangeville to Kooskia
• 5 Clark Fork Highway SH-3: Sandpoint to Montana
• 6 Clearwater Highway SH-11: Greer to Montana
• 23 Coeur d'Alene-Yellowstone Trail US-10: Washington to Montana
• Craigmont-Kamiah Highway?? SH-12: Craigmont to Kamiah
  • Former 24A Nez Perce Branch of the North and South Highway: Craigmont to Nezperce
• Colburn Culver Road (SH 55):
• Cooley Road
• Cotton East Road
• Cub River Road
• Dayton-Red Rock Road (SH 35): included Oxford-Red Rock
• Deary-Bovill Road
• Declo-Albion Highway, formerly 4 Cassia Highway SH-77: Albion to Declo
• Dufort Road
• East Branch Road SH-57: included Priest River-Coolin
• East-West Road? included Fairfield
• 7 Elk City Highway SH-14: Harpster to Elk City
• 8 Elk River Highway SH-7: Orofino to Santa
• 34 Elk River Extension SH-7: Nezperce to Orofino
• Enaville-Murray Highway
• Fairfield-East Road
• Fairfield-West Road
• First Street-Iona Road
• Genesee-Thorn Creek Road?
• Georgetown-Nounan Road
• Glenns Ferry-East Road
• Gooding-Fairfield Road?
• 10 Grace-Preston Highway SH-34: Preston to Alexander
• Grace-Turner Road
• Grangeville-Craigmont Road
• Grangeville-Harvard Highway: included Harvard-Deary
• 11 Gray's Lake Highway SH-34: Soda Springs to Wyoming (earlier Soda Springs to Idaho Falls)
• Green Creek Junction-Reservation Line Road
• 12 Heyburn Park Highway SH-5: Plummer to St. Maries
• 13 Idaho Central Highway SH-22: Mountain Home to Trude
• 14 Idaho-Montana Highway US-91: Idaho Falls to Montana
• 15 Idaho-Oregon Highway SH-19: Oregon to Caldwell
• Ketchum-Clayton Highway (appears to be another name for part of the Sawtooth Park Highway)
• 38 Kootenai Highway US-2: Bonners Ferry to Idaho
• 18 Lemhi Highway SH-28: Roberts to Salmon
• 19 Lewis and Clark Highway SH-9: Washington to Montana
• Lewiston-Orchards Road is another name for Thain Road.
• 20 Lost River Highway SH-27: Challis to Moreland
• 21 Malad Valley Highway SH-36 → US-191: Utah to Downey
• McCammon-Robin Road: included Robin-Arimo
• Middleton-South Road
• Minidoka-Kimama Road?
• Montour-Ola Road: included Sweet-Ola
• 22 Moscow-Bovill Highway SH-8: Moscow to Bovill
• Mountain Home-Grandview Road: included Grandview east
• Nampa Road: included Boise-Nampa (US 30)
• Nez Perce Highway SH-62: included Craigmont-Mohler
• North Bench Road
• 9 North Side Highway SH-25: Gooding to Rupert (earlier Declo?)
• 24 North and South Highway US-95, US-95A: Weiser to Canada
  • Copeland-Porthill Branch SH-1: Copeland to Canada
• North Yellowstone Highway?
• 16 Old Oregon Trail Highway US-30, US-30N: Oregon to Wyoming
  • 17 Ontario Branch US-30: Oregon to Fruitland
  • 40 Southern Branch US-95, SH-18: Fruitland to Blacks Creek
  • 41 Bancroft Loop: Lava Hot Springs to Lund
• 33 Oneida Highway SH-37: Malad to American Falls
• Ora Road: included west from Ashton
• 25 Owyhee Highway US-95, SH-20: Oregon to Nampa
• 37 Palouse Highway US-95: Potlatch to Coeur d'Alene
• Parma-Wilder Highway
• 26 Payette Highway SH-15: Boise to New Meadows
  • Emmett Branch SH-16: Emmett to Horseshoe Bend
• Payette-Emmett Highway SH-16: Payette to Emmett, branch to New Plymouth
  • Former? Emmett-New Plymouth Highway: Emmett to New Plymouth
• Pine Creek Road
• Pingree-Thomas Road
• Preston-Bear River Highway
• Priest River Road SH-57:
• Reservation Line Road
• Rexburg-Parker-St. Anthony Road: included Parker south
• Ririe-Beeches Corner Road
• Roberts-Ririe Highway SH-48: Roberts to Ririe
• Roberts West Road
• Robin West Road
• Rock Creek Road (SH 47): east of Ashton to Wyoming (Cave Falls Road), removed 1951
• 27 Roosevelt Highway SH-24, SH-39, SH-29: Bliss to Wyoming
  • Former 2 Bliss-Shoshone Highway: Gooding to Shoshone
• Round Valley-Cascade Road
• Sagle-Midas Road (SH 56):
• Salmon River Highway?
• Salmon River North Highway?: included Riggins-Whitebird
• Samaria Lane Road
• 28 Sawtooth Park Highway US-93: Nevada to Montana
  • Blue Lakes Spur: Kimberly Road to Addison Avenue in Twin Falls, created 1953
  • Richfield Branch SH-23, SH-22: Shoshone to Bellevue
  • Richfield Spur (SH 76):
  • Twin Falls Loop SH-26: Godwin to Twin Falls
• Schiller-Arbon Valley Road?
• Sharon-Ovid Road
• Shelley-New Sweden Road
• South Yellowstone Highway SH-33: Rexburg to Wyoming
• Spirit Lake Highway SH-41: included Ross Point-Rathdrum
• 39 State Line Highway SH-40: Wyoming to Wyoming via Geneva
• 29 Teton Highway SH-32: Tetonia to Ashton
• Thain Road: Lewiston to Richardson Avenue, removed 1951
• Tin Cup Road
• Triumph Mine Road: Gimlet east, removed 1951
• 30 Twin Buttes Highway US-20: Arco to Idaho Falls
• Ucon-West Road
• Victor-Irwin Highway
• Wapello to Firth Road
• Wayan to Freedom Road
• Wood River Road
• Worley-State Line Highway SH-58: Washington to Worley
• 31 Yellowstone Park Highway US-91, US-191: Utah to Montana
• Yellowstone-Sun Valley Highway

What was the name of SH-6, Washington to Potlatch?