the army, who may or may not know a thing or two about walking, says the average is 4 km / hr. which according to the tubes is 2.48 mph.

army

see graph at "dismounted movement".

that's flat terrain.

now if you are going uphill or downhilll - my favorite - see same chart for added or subtracted times.

for me, they can be very close to reality when planning for a hike.

pack weight can influence speed / times as well - as does everything else mentioned in previous posts.

good topic.