We took a little trip over to the east side of the Sierra Nevada (in California) last weekend. Since I am an early riser, I got out of bed one morning while it was still dark outside and the family was asleep, and hiked to Heart Lake above Mammoth Lakes.
The lake is not very big and the hike (from the campground and small ghost town above Lake Mary) was maybe a bit over a mile long (each way) with a gain in altitude of maybe 500 feet. The air was cool, changing from the mid 50's at the paarking area to just at freezing at the lake (at around 9,300 feet). But I loved the hike. The air was fresh and the view of the rising sun reflecting off the rim of the Sierra was impressive.