11 miles, 18 km. Not a big deal. If I can do it a 3 mph, shouldn't take more than 4 hours. Highest elevation is 800 feet, 250 m. Easy, right?
The guy who gives me a ride part-way from Hanalei towards the start of the trail says you can do the trail in 5 hours if you're unloaded and going fast.
On my way out, I run across a guy who's obviously going in and out in a day. He only has a small fanny pack, has water, and probably little else. I greet him, but he's so focused he ignores me.
On my way in, I left Ke'e Beach (the start of the trail) around 10:30, settled in on Red Hill (a mile or so shy of the beach) around 6pm, when it got dark. Can you say 1mph? I don't know how heavy my pack was, probably 50+ pounds.
On my way out, with a lighter pack, I left Kalalau beach (trail's end) at 4pm, camped at sundown around the 8-mile marker (3.5 miles from the start, probably 6pm). 1.25 mph?
I left around dawn (6am?) the next morning, had covered the remaining 8 miles by about 2:30pm (including maybe an hour stop for lunch at Hanakapiai beach). 1mph and with a light pack. Amazing.
Why do I think people walk at 3mph or 5Km/h? How do people walk a 26-mile marathon in 6-7 hours? And it's not just me -- I was one of the faster people on the trail.
Certainly the many up- and down-hills don't help, nor does the abundant mud, nor the time we stop admiring the view. The fact that even our "light" packs are still heavy probably doesn't help either. I'm going to start using 1mph average when planning for backpacking trips with a heavy pack.