State index
Idaho
Route 20 gateway for Idaho from Island Park through Rexburg, Idaho Falls, Boise, Caldwell, and Parma, with Oregon handoff coverage beyond the state line.
Idaho
Idaho is the next westward state after the Yellowstone-side connector. Use it when you want the first practical Idaho layer after the west re-entry, and keep the Pacific-facing Oregon finish in view.
Cross-country role
Idaho is the reset state between the Yellowstone-side handoff and the Pacific-facing Oregon finish. In the full Miami to Boston to Route 20 journey, Boise is the major city anchor that makes the western continuation easier to pace.
For Yellowstone approach and west re-entry planning, start with Island Park and Ashton, then continue toward St. Anthony and Rexburg.
Best ways to use Idaho right now
Best Idaho weekend
Fairfield to Caldwell Route 20 Weekend
Use this weekend first if you want the clearest broader Idaho outing before stepping into the newer Oregon continuation.
Best Idaho section
Fairfield, Mountain Home, Boise, and Caldwell
Use this section if you want the clearest Idaho west-approach continuation beyond the earlier interior Idaho stretch.
Best final Idaho handoff
Parma
Use Parma when you want the clearest final Idaho-side stop before the Oregon state line.
Best re-entry context
Island Park
Use Island Park when you want the quieter first Idaho continuation immediately after the west-side Yellowstone handoff.
Why Idaho matters on this site
Idaho matters because it turns the Yellowstone west re-entry into a real next-state continuation instead of a standalone park-edge note. The current Idaho build is still intentionally small, but it now gives the route a usable westward foothold beyond Island Park.
This Idaho page is intentionally bounded to the first stretch west of Yellowstone. It begins with Island Park and now reaches Ashton, St. Anthony, Rexburg, Idaho Falls, Arco, Carey, Picabo, Fairfield, Mountain Home, Boise, Caldwell, and Parma before handing the route off into the first live Oregon continuation.
Current Idaho route section and towns
Read these from West Yellowstone and Island Park through Parma when you want Idaho to feel like one connected continuation rather than separate bundles.
Current guide
Rexburg, Idaho Falls, and Arco
Current broader Idaho section on the site, carrying the route west from Rexburg through Idaho Falls to Arco.
Current guide
On Route 20
Island Park
Quiet Idaho-side continuation town that keeps the route readable after West Yellowstone.
Current guide
On Route 20
Ashton
First fuller Idaho gateway town on the route west of the park-side continuation.
Current guide
On Route 20
St. Anthony
Practical middle Idaho stop that makes the continuation from Ashton to Rexburg feel more usable.
Current guide
On Route 20
Rexburg
Strongest current larger Idaho base on the site.
Current guide
On Route 20
Idaho Falls
Larger practical city stop that gives the Idaho build a stronger middle anchor.
Current guide
On Route 20
Arco
Current handoff point from the earlier central Idaho build into the broader interior Idaho continuation.
Current guide
On Route 20
Carey
Practical smaller stop that keeps the interior Idaho continuation readable west of Arco.
Current guide
On Route 20
Picabo
Smaller continuity stop that helps the Idaho corridor feel more connected on the way to Fairfield.
Current guide
On Route 20
Fairfield
Current handoff point from the interior Idaho build into the newer west-approach continuation.
Current guide
On Route 20
Mountain Home
Practical transition town that turns the Idaho corridor toward the Boise side of the route.
Current guide
On Route 20
Boise
Strongest larger-city anchor on the Idaho side of the route.
Current guide
On Route 20
Caldwell
Idaho-side handoff town where the route turns toward the Oregon border.
Current guide
On Route 20
Parma
Final Idaho-side continuation town before the Oregon stretch begins.
Best current Idaho trip and next pages
Best Idaho weekend
Fairfield to Caldwell Route 20 Weekend
Use this weekend if you want the clearest broader Idaho outing before stepping into Oregon.
Best next state layer
Oregon
Use Oregon when you want the first continuation beyond the Idaho border through Nyssa, Ontario, and Vale.