Mill Creek is a very challenging uphill ride if you are coming from sea level. The tread has a few baby rock gardens that were challenging to navigate with no oxygen in the lungs. However, grunt your way through Mill Creek to Colter's Escape heading to Peaked and the views of Grand Tetons are well worth the grunt up Mill Creek. Of course, then you get to come down what you just ascended at the end, which was a hoot. Just watch for horses on this trail.