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Gambit McCrae
08-25-2014, 10:23
I have been looking at some mileages both on atcalc (http://www.atdist.com/atdist?k1=AT&k2=AA&h=d658425a&year=2014) as well as THIS (http://rohland.homedns.org:8008/at/state/state_detail/AT_state_detail.aspx?stateID=5 &sectionID=33)

If we look at the section 16 and 17 that website has it as 16.5(sec 17) and 11.9(sec 16) total of 28.4

When I lookup those sections on atcalc i get 21.1. A 7.3 mile difference. Are my calcs correct or am I missing something? Not saying that atcalc is wrong, just wanting to find the accurate site.

Note: The other website hasnt been updated since 2013. Might have been a reroute in there somewhere?

As well, atc.com (http://www.appalachiantrail.org/about-the-trail/terrain-by-state/georgia) has the GA section marked at 76.4 where as atcalc has it at 78.5 from springer to nc line

Just some interesting data questions is all, not trying to poke at anyones mileages

Traveler
08-25-2014, 11:34
For what its worth, I have noticed the mileages on signs to be in disagreement with the AT trail book at times. Even using GPS on the same trail I find the distances to be different just because I walked a zigzag course to avoid puddles on a trail. So I look at these mileage statements as guidelines and approximations. With relocations (even several very minor moves around deadfalls) can add or subtract to the total "official" trail.

That said, I have always wondered if any of the mileage indicators took into account horizontal mileage combined with vertical mileage. If you walk a full statute mile on level ground, the same mile on even a mile 7% grade will be longer. Could that be a reason, that one of these has used a formula for vertical and horizontal mileage?

10-K
08-25-2014, 11:40
The trail is measured with a wheel I'm pretty sure so the elevation changes are factored in.

Gambit McCrae
08-25-2014, 11:46
The trail is measured with a wheel I'm pretty sure so the elevation changes are factored in.

How often though 10-k? once a year? 1940? lol

Traveler
08-25-2014, 11:54
The trail is measured with a wheel I'm pretty sure so the elevation changes are factored in.

You would think so, but in all the times I have discussed this with Park Service people, retailers, GPS manufacturers, no one can tell me if thats true, nor do they know how to assess the rise/run/slope measurement of each grade you go up or down. A Garmin rep once said they were working on something that would marry with a topo map and provide that in two separate screens (map miles and another on actual miles), however I have not heard anything about it.

10-K
08-25-2014, 11:59
Beats me but I'd go with the "approximately 2180 miles" figure given on the ATC website.

Nooga
08-25-2014, 12:40
i would use the ATC data. I'm sure that when ever the trail is rerouted, that section is measured. The question though how current is Data Book and does it reflect all the reroutes?

Gambit McCrae
08-25-2014, 12:43
10-k Im good with callin it a total 2180 OVERALL, what I need confirmation on is the breakdown by section. I need to know if a section is 10 miles or 17 miles, and where that data is the most accurate at.

Example: Last year I did MD. My data showed 40.9 miles. In two data sources. But my friend who had hikes from springer to Damascus in 2013, his data showed it as just over 50 miles for the state of MD.

10-K
08-25-2014, 12:56
What were your data sources?

Your friends?

Gambit McCrae
08-25-2014, 13:16
What were your data sources?

Your friends?

No sir, I used the 2014 thru hiker companion, the ATC map set, and I believe the WV MD data book that comes with the map set. My mileage was correct. He had an older data book from 2007 I believe, But that were still 10 miles off from one another which seems like a long reroute

10-K
08-25-2014, 13:32
No sir, I used the 2014 thru hiker companion, the ATC map set, and I believe the WV MD data book that comes with the map set. My mileage was correct. He had an older data book from 2007 I believe, But that were still 10 miles off from one another which seems like a long reroute

I'd go with the 2014 information. If my memory is correct almost 2 miles of trail were added just to create switchbacks on the south side of Roan Mountain and that's just 1 side of 1 mountain.

If it really bugs you email the organization who maintains the trail in that area and ask them - they'd know.

Gambit McCrae
08-25-2014, 13:44
I'd go with the 2014 information. If my memory is correct almost 2 miles of trail were added just to create switchbacks on the south side of Roan Mountain and that's just 1 side of 1 mountain.

If it really bugs you email the organization who maintains the trail in that area and ask them - they'd know.

I am a weekend hiker, and like to push as many miles as I can. I can se how this would be less imporntant for a thru hiker, but for someone who is only out for 2-3 days at a time, and already trying to push a 24 mile day, every mile counts at the end of the day