Could trail creek pass road through sun valley a legitimate route to get to northern access to the copper basin area for a northern overnight approach to Smiley Mountain? Looks like it would be more scenic than driving through Arco and according to google maps (questionable reliability) it's about 15 minutes faster.

Anybody been on this road before and could offer some insight?

Trail Creek Pass road is the best access to Copper Basin. Please note that the road on the west side is a one lane, gravel, 25 mph washboarded road. Trailers are not recommended.

I like doing it as a loop by going up Trail Creek and then if you're going south, come back through Arco, The Craters, Fairfield, etc. Trail Creek varies depending on how soon you drive it after it's been graded and whether it's wet or not. When it's dry you might leave a mile long dust cloud behind your rig. It's passable by most any vehicle but as I always say, "carry a full sized (inflated) spare, know where your jack is and don't forget the lug wrench."


Bob

You can reach Copper Basin from Antelope Pass also, but it'll probably be much slower. I drove home that way a few weekends ago. The southeast side of the pass is steep, windy and very narrow and there's a washout lower down that definitely required high-clearance. Not sure that I'd drive that way again, but it was nice to see some new country.

It depends on where you're coming from, Highway 75 to ketchum is pretty crapped up with tourist traffic this time of the year and the 26 mile drive to town from the Highway 20 turn off can be tedious.
I was over Trail Creek a few days ago, the road from Ketchum to Kane Creek (almost to Copper Basin) is pretty jacked up with washboards but from the Highway 93 side it's in
Really good shape all the way to the basin turn off. Conditions on Copper Basin Loop road to Lake Creek aren't very pretty but they rarely are. If scenery is a motivator, go through Ketchum, the Lost River range is nearly invisible with all this smoke.