Any high mountain passes through Montana/Idaho on I-90
Headed to South Dakota from Portland, OR along I-90, curious if there is any high mountain passes like on I-70 through Colorado?
Forum Discussion
There are a couple of summits in Idaho, including the one on the ID/MT border, and couple in Montana. The intersection of I90 and I15 is at Butte, a relatively high mining town. But none are as high as the 2 on I70. Of course to get a realistic picture you need to know the total length of climb and grade for each, not just the absolute altitude (compare Portland to Government camp v Denver to Eisenhower tunnel).
