Now we're on an old section of US10, just south of I-90, right after exit 38.
This was definitely US10, which makes it almost definitely Yellowstone Trail.
FILE NAME: P1040335.JPG | DATE: 3/27/09 2:57 AM | CAMERA: Panasonic (DMC-TZ4) | RESOLUTION: 3264 x 1840 | NATIVE FOCAL LENGTH: 7.1mm | FLASH: Flash did not fire, auto | EXPOSURE TIME: 1/125 sec | METERING MODE: Multi-segment | EXPOSURE MODE: Auto exposure | APERTURE: F4 | ISO SETTING: 100