Kelly Lake Trail is a 14.9 mile loop trail located near Gilroy, CA that features a lake and is rated as difficult. The trail offers a number of activity options and is accessible year-round.
There are a number of ways to get from the two most appropriate trailheads (Hunting Hollow and Coyote Creek) to Kelly Lake. The paths with the easiest grades are the fireroads and are favored by the cyclists, but there are plenty of other trails. My group went over Willson Peak on the way there, and came back along Grizzly Gulch. The trails tend to be quite steep, but the views are lovely. Kelly Lake itself is pretty enough. Certainly we weren't bothered by bugs, though the frogs sang pretty much all night.