The Lafayette reservoir is a popular hiking area in the Lamorinda area. The easy paved path around the reservoir gets crowded with joggers, dog-walkers and weekend relaxers.
Upper trail provides a more scenic and quiet loop (5miles) with some nice steep stretches.
Since I never exactly mapped or measured the path, a GPS record is the best record for distance and effort.
You may also meet a friendly snake along the path.
here's the map
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