Back in the early 90`s when GPS was new to me. I hiked from the porch where most pay a toll to property owner to the Anaversary pool with a Magellan tracking GPS device. The first time I hike in it. Read 1.85 miles. The altitude read 4,444 at the ranch. At the Anaversary pool it read 3,566 feet.
The next trip it said it was 1.92 miles. I must have stopped to pee or something that made the difference? Also I measured from the lower parking lot where most park. It read 1.65 miles. The altitude there was a little more than 140 or 150 feet lower there. I can not remember that good. Perhaps some one should go out there an check again.
Judging by the recent reports from the news articles posted here. A lot of inexperienced hikers have not been able to hike that far. So saying it is a little less than 2 miles is approximately true. It could be even further if you get side tracked by butterflies or birds or the intense beauty of your surroundings.
Be smart and hike safe every one.