Accuracy of trail distances on signs and in guide books

[Pete_Hickey]

Since there is no fundamentally correct length one cannot compute an absolute accuracy, so the general concept will have to do...

Which leads me to a totally different method that guide books should use to describe trail lenghts.

Define a well-known easy trail as type I. The book says that type I trails are n sortof miles per hour. Another well known trail is defined as type II which are n+delta sort of miles per hour.... Continue up until type X trails. Note that type X trails are the most difficult possible by a human.

Then, each trail is designated with a number of its diffuculty, and its sortof distance.

The sortof distance doesn't have to be that accurate, since the difficulty level is going to have more effect on time.

Of course, this doesn't work for people who want distance as bragging bits....but then again..... there would be something new to brag about.

"I did 2 miles of a type VIII trail!!!"

Doesn't that sound better than someone saying that they did 11.625 miles?

 

[Remix]

Its kind of ironic that this question-- expressed as a the length of border between two countries-- was used as by Mandlebrot to investigate and define chaos.

The mathematically precise distance between two points on a hike is infinite, lol.

From a practical point of view I think Pete Hickey has the best answer. Approximate distances and trail conditions are more important than accurate distances.

 

[bikehikeskifish]

Seems to me we have had this conversation more than once in the past...

Oh at least once or twice. Did we agree last time too?

some of the trails in the Waterville? area were being GPS mapped.

The GPS map of Waterville was the basis for the new XC trail maps, and it is a very nice map indeed. The old XC map didn't show elevation in any way. It's kind of neat to be able to figure out the distance and the elevation skied.

(It's almost "that time" too!!! )

http://www.waterville.com/info/nordic/nordicmap.asp

The high-res PDF is available from the above link too.

Tim

 

[jniehof]

The GPS map of Waterville was the basis for the new XC trail maps, and it is a very nice map indeed.

I'm not familiar with the XC maps, but the new hiking map was GPS surveyed and produced by the same cartographer who did the Sandwich Range map. I suspect this means the Sandwich Range and Waterville Valley maps have *two* high-resolution GPS surveys--the AMC's and Mike Bromberg's.

 

[pks4000]

Distance

You all raise some good points and counterpoints.

For decades I have used effort required as the true measure of a hike/climb.

I have found that for the most part, the vertical rise is the effort indicator and the distance the determination of extra effort whether its measured Pathagorically or horizontally.
Once you "get on" the mountain if you do 1000-1400 vert feet an hour that's pretty good and most of us can sustain that for a few hours (Think Madison/Adams)

The distance gives me an idea of "on mountain" grade (1 mile and 1000 vert is steep stuff) .....not talking about approaches here.

So I can see where the scientific debate is interesting, but in the field its not the distance, but the effort composed of vertical and distance. Of course here we leave the altitude effect out of the effort.

 

[wardsgirl]

Interestingly enough, in the Whites, 300 of my steps always equals 0.1 mile, but on Vermont's Long Trail, it took at least twice that many steps to travel the same distance....

 

[bikehikeskifish]

For decades I have used effort required as the true measure of a hike/climb.

How do you express effort required?

As I mentioned above, with only one or two exceptions, my 26 trips to bag 48 WMNF 4Ks indicated all hikes were on equal footing, effort-per-hour-wise with the variation being the number of hours involved (correlating to the length of the trail.) I make this assertion on the fact that unless I hiked with someone who was much slower than myself, or I took an extra long break on a summit, I averaged 1.5MPH +/- .1, and 485FPH +/- 25. Owl's Head and the Bonds get better average speeds since they have 10 miles of flat (Wilderness Trail.) Wildcat Ridge Trail is slower being perhaps the steepest of the lot.

This applies only to the Whites. The ADKs with their longer approaches would be different, although probably equally formulaic.

Tim

 

[RoySwkr]

Many winters ago I hiked up the lower Crawford Path and caught up with Brad Washburn and his wife who were measuring the trail with a tape, they said it was easier in winter because the tape got caught on fewer things. (This trail segment was not on his map but he wanted the distance.) She got cold so I helped him tape the last section up to Webster Cliff Trail.
Just before the junction was a patch of scrub with an opening on each side, and in the snow it wasn't obvious which side the official trail went on. He said he would have to come back in summer to finish the measurement although the difference in distance might have been all of 10 feet.

"Dead Reckoning" would in my opinion be a waste of time. In rugged terrain maintaining an even stride, let alone counting it, would become impossible. That method is generally only used, in surveying at least, for shot 'guestimates' when attempting to locate or measure something quickly to get a rough idea of where something should be or how far away from another point you are.

Yeah, but how accurate do you expect the guidebook to be, surely not the standards of a land survey? I have found plenty of geocaches by pacing distances. If you use time instead of distance for dead reckoning, any errors by the measurer may be cancelled becuase the user is also too slow/fast there.

I believe a wheel has been the historical practice. The pre-electronic alternatives would be surveying or tape measure and compass + inclinometer. (I believe tape measure and compass + inclinometer are still used in caves.) A wheel would simply be quicker and easier.

I believe that WMG distances are based almost entirely on wheel distances, many done by John Burroughs who was editor before Steve Smith, with the GPS tracks used only for maps. The next guy to talk to Steve can ask him.

Caves are mapped with a variety of methods depending on how large and straight the passages are and how accurate the result must be, but yes tape and compass/inclinometer are still used sometimes. Even GPS and air photos are used, to locate entrances and provide a loop closure between multiple entrances.

Do you know if trails in the Whites have been GPS mapped and if so, which ones (in a general sense--I'm not looking for an exact list)?

I believe all of them.

That depends on your definition of "trail"

When the Owls Head controversy arose, people claimed the trail must go to 4025 because that's what the new "super-accurate" AMC maps showed. Of course it did not, and the excuse given was that wasn't an "official" trail so it wasn't GPS-ed but just drawn in. A similar thing happened with Mt Davis. Since these "non-trails" are shown on the map with the same sort of line as genuine trails, the user has no way of knowing which are GPS tracks and which are somebody's fantasy.

I have always wondered what the people who hiked "all the trails" did about mapped trails that didn't really exist, presumably they were in such a hurry that they didn't notice

It was my understanding that (at least for the last two editions) the AMC trail maps were based on all of Larry's GPS work. At the very least Larry Garland has the distinction of being one of those who has hiked every trail in the WMNF.

I think the article on Larry Garland said he did only 20% of the trails on AMC time, the rest on his own presumably without the mapping-grade GPS. The other trails were mapped by other people with varying degrees of ability.