From the trailhead, follow an old road to the Trinity Alps Wilderness boundary at Cherry Flat. Climb gradually along the Stuart Fork of the Trinity River.
After 4 miles, the trail crosses Deep Creek over a bridge and then crosses Oak Flat.
At 5 miles, pass the turnoff for the Alpine Lake Trail
. The trail continues to climb gently, crossing Deer Creek over a bridge at around 7 miles. Pass the junction with the Deer Creek Trail
at 8 miles and reach Morris Meadow at 9 miles.
Morris Meadow has awesome wildflower displays all summer and plenty of campsites.
Beyond the meadow, the trail turns west into more mountainous territory. At 12 miles you'll reach Portuguese Camp, the last good spot to camp before Emerald and Sapphire Lakes
The trail becomes steep and open as it climbs west toward Emerald Lake. Emerald Lake is actually man-made, created for mining operations a century ago. There's still a lot of old mining equipment lying around.
Follow the cairns around Emerald Lake's north shore and then climb 600 feet to the trail's end at Sapphire Lake. At the deep, clear lake, enjoy the views of Thompson Peak and the Sawtooth Ridge.