usa interstate steepest grade
I gotta agree with you Larry. The Eisenhower tunnel grade is pretty **** steep on the west side too ... and long. I'd have to rank em this way ... Eisenhower tunnel, Freeway that traverses the Smokey Mts., and then the Grapevine. I'm sure there's others, but my poor ol 32' V10 SeaView by National huffed and puffed over all three of those last summer, Ike definetely got it panting more than the other two. Elevation may be a factor too, Denver is what? 5,000' or so, the Ike tunnel, I believe, is pretty close to 11,000.
We stayed at Breckenridge (in the Ike tunnel neighborhood) for Thanksgiving. That was 11,500'. Talk about altitude sickness! Constant headache, pant like hell climbing stairs, big time insominia, (lay in bed all night long and concentrate on your next breath!)