I hiked as far as the bridge, about a mile from the trailhead start at Happy Isles. The elevation gain was about 300 feet. From my standpoint it sucked that you would gain some elevation on the trail and shortly thereafter it was down hill so you had to regain elevation time and again. I decided that continuing on the Mist Trail to the top of Vernal Falls (or even further to Nevada Falls) wasn't in the cards this visit.