Giant Sequoia National Forest. Thirteen interpretive stations along the mile-long Trail of a Hundred Giants introduce visitors to a splendid grove of sequoias between 500 and 1,500 years old. The trailhead, in the southern part of the Monument, is on the Western Divide Highway (a continuation of Highway 190), just across the road from Redwood Meadow Campground.  With a diameter of 35 feet, the 269-foot-tall Boole Tree is, by volume, the largest tree in the Monument and the 6th largest tree in the world. It was named for the lumberman who cut all the nearby trees-and spared it-about 100 years ago.