There are LOTS or references to "tea breaks" among the voyageurs and the
trappers of Canada and Alaska (mostly Canada), (see, Men of the Last Frontier,
 by Grey Owl).

However the distance traveled would have been much different on snowshoes, by
dog sled, and on "shanks mares." I suspect that the reference is just one of
the slang expressions to indicate a long distance.

Les Buell