Heart Lake is a beautiful lake located south of Sherwin Ridge above the Mammoth Lakes Basin. The lake is a fairly shallow lake. From above the lake you can see the bottom of the lake very easily. The lake is small enough that it takes a good breeze to blow the glassy surface off.
The Heart Lake Trail begins at the end of the Coldwater Creek Campground. The trail passes an old mining camp and the remnants of an old stamp mill. The trail then begins to ascend the side of Sherwin Ridge. This is the same trail that is described in the Pyramid Peak Hike. The trail has two switchbacks on it. At the second switchback the Pyramid Peak route splits off to the left and the Heart Lake Trail heads off to the right.
Much of the remainder of the trail has no tree cover. If it's a warm day you will feel it through this section as you continue heading uphill. As you reach the trees you've been looking during the long straight section of trail, the lake is just behind the trees.
A couple of things to take note of: During the months of June and July the mosquitoes are fierce on this trail. You will want to use heavy Deet for this hike. Also, the trail is heavily used by Mammoth Lakes Pack Outfit for short out and back trips. That mean you may have to step off of the trail to let a long train of horses. It also means that there will be lots of horse dung along the trail.
If you are really feeling energetic and want to turn your trip to Heart Lake into a real adventure you could head up along the route to Pyramid Peak. When you reach a saddle between two red peaks you can drop off the south side of the ridge and scree ski your way down the slope toward Heart Lake. I'll include a track log that includes this entire trek plus some extra credit. Enjoy.
Check out the Official Route and Triplogs.