Took Stone Canyon trail up Mount Lukens to train for an upcoming seven-day backpacking trip to the Eastern Sierra in August. Did it on a gloomy, overcast morning in May with temperatures in the mid 50s. With a light backpack of only about 10 lbs I reached the summit after about 2 hours 15 minutes and back down in another 1 hour 15 minutes. 6,400 feet elevation gain and loss and 8 miles in and out in 3.5 hours. Will repeat with heavier backpack very soon.