Derek Pullem
Donor
It's also a question of motivation. Harold Godwinson covered 185 miles to Stamford Bridge in four days and his army arrived in battleworthy condition.
The numbers I've seen suggest it was about a week to go 200 miles from London to Stamford Bridge. Still impressive. On the return (that may be only the mounted infantry component of the army at Stamford Bridge) the distance was also covered in about the same time.
The march to Hastings was around 20 miles per day - again taxing for a foot soldier but less so for a mounted infantryman.