On a paved surface and not really any stops, I figure about 3-4 mph - 4 if I push myself a bit, 3 if I don't. On an uneven trail maybe 2 mph or even less if there are things to stop and see. I know that backpacking, we're a lot happier at 6-8 miles a day which gives plenty of time to sight-see and set up camp in the daylight.

Well i do not think that i can have walking speed of 6 miles per hour . It is beyond my walking speed . I can hardly walk for 8 km/hour .

Have you never come across Naismith's rule? Perhaps it is just a British thing.

Naismith's Rule

3mph on average, myself.

On a side note: In my research for a trip to New Zealand, I found it interesting that many hiking trails (known as "tramping tracks") have signs that are marked in times, not distances. Interesting, no?

Wow, some of my mid-hike naps are longer then that!