Updated 4 September 2023
The Lake Margaret trailhead is 5.2 miles west of Carson Pass on Hwy 88, just past the western end of Caples Lake (if you reach the Kirkwood Resort, you have gone too far). The trail passes a variety of pleasant scenery, before arriving at Lake Margaret, a lovely alpine lake with rocks for climbing and swimming. It is an excellent day hike for a family. No wilderness permit is required to hike here, but camping requires a California Campfire permit, available here (although note that in recent years wood and charcoal fires are prohibited in the South Tahoe area — backpacking stoves only).
The hike is 4.8 miles round trip, with 550 feet elevation gain. On your first hike, though, a GPS is recommended to not lose track of the correct trail.
Here is a map of the hike:
Here are two photos of Lake Margaret:
