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#56444 - 10/14/19 10:07 AM Measured elevation gain/mileage MWT from the portal
Kascadia Offline


Registered: 07/23/18
Posts: 24
Loc: PNW - Cascade Foothills
Hello - I just saw a post that stated the total elevation gain for Whitney (from the Portal on hiking trail) was 7000 ft. I was curious to get various readings of mileage/elevation gain from people that have done this. I know the standard description is 22 miles/6000 ft, but wonder what numbers people log with various tracking devices. Thanks for the info!

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#56445 - 10/14/19 11:33 AM Re: Measured elevation gain/mileage MWT from the portal [Re: Kascadia]
KCMasterpiece Offline


Registered: 02/14/19
Posts: 17
Loc: California
Everyone's will vary some.

My device said 6,409 feet of elevation gain and 11.3 miles from portal to the top, and 239 feet of elevation gain on the way down for a grand total of 6,648 feet over 22.6 miles. Others have had shorter distances recorded I know.

Also of interest, my GPS said the summit was 14,478 feet, but it's similarly a little off on other mountains as well.

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#56446 - 10/14/19 12:19 PM Re: Measured elevation gain/mileage MWT from the portal [Re: Kascadia]
StorminMatt Offline


Registered: 06/20/19
Posts: 46
Loc: Norcal
7000ft is WAYYY off. Given that the trailhead elevation is 8360ft and the summit is 14505ft, you have a net gain of 6145ft. Add in elevation losses that must be regained such as the drop into Bighorn Sheep Park and the drop after Trail Crest, and 6400ft of elevation gain looks about right.

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#56447 - 10/14/19 12:41 PM Re: Measured elevation gain/mileage MWT from the portal [Re: StorminMatt]
bobpickering Online


Registered: 02/07/10
Posts: 458
Loc: Reno, Nevada
I just plotted the route on CalTopo and got 20.12 miles and 6,902’ gain, round trip. The CalTopo route consisted of a gazillion individual points. I think that CalTopo just adds up the horizontal distance and elevation gain for each segment of the route. GPS altimeters aren’t very accurate, and barometric altimeters are even worse. I would trust CalTopo over my altimeters, so I don’t think 7,000’ is very far off.

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#56451 - 10/14/19 03:45 PM Re: Measured elevation gain/mileage MWT from the portal [Re: StorminMatt]
John Sims Offline


Registered: 04/20/12
Posts: 555
Loc: Sunnyvale, California
Originally Posted By: StorminMatt
7000ft is WAYYY off. Given that the trailhead elevation is 8360ft and the summit is 14505ft, you have a net gain of 6145ft. Add in elevation losses that must be regained such as the drop into Bighorn Sheep Park and the drop after Trail Crest, and 6400ft of elevation gain looks about right.


Matt, you are overlooking the fact that you lose the gain twice. One on the way up, and once again on the way down. 7K may not be "exactly" right, but very close. Trail Crest is 13,600 +/-, Intersection with Muir Trail is at 13,400 +/- two ways = 400', Outpost camp not much, but many small up's and downs adds another 200' each way, so 400'. Those two issues account for additional 800', so conservative estimate would be 6145 + 800 = 6945. Also, not likely you parked level with trail head, so add a bit more, and Shazam, you get pretty much at 7K'. That is what my Garmin indicated the last time I hiked the main trail.

Also, see Bob's post above. His is likely more accurate. If so, roundtrip would get WAYYY over 7K:-)

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#56452 - 10/14/19 06:51 PM Re: Measured elevation gain/mileage MWT from the portal [Re: John Sims]
bruce Offline


Registered: 09/27/13
Posts: 130
Loc: Novato, CA
I think it's around 6900 feet of ascent (up and down). There is around 300 feet of additional ascent from just before Trail Crest to the summit. So that x2 plus a 30-40 ft. ascent leaving Outpost and a few little humps and you can get close to 7000 feet. But my guess is 6900 feet.

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#56453 - 10/15/19 09:40 AM Re: Measured elevation gain/mileage MWT from the portal [Re: bruce]
Eugen Offline


Registered: 01/01/18
Posts: 5
Loc: Oregon
I think the confusion because different people have different length of their feet. In meters the gain between Portal and the top gave me 2056 meters

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#56454 - 10/15/19 03:43 PM Re: Measured elevation gain/mileage MWT from the portal [Re: Eugen]
bruce Offline


Registered: 09/27/13
Posts: 130
Loc: Novato, CA
Originally Posted By: Eugen
I think the confusion because different people have different length of their feet. In meters the gain between Portal and the top gave me 2056 meters


Since the net gain is 6145 feet, 2056 meters between the Portal and the top is 6745 feet. It would mean there is 630 feet of elevation loss along the way. I don't think there is nearly that. Perhaps 400 feet at the most.

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#56455 - 10/15/19 06:36 PM Re: Measured elevation gain/mileage MWT from the portal [Re: bruce]
bobpickering Online


Registered: 02/07/10
Posts: 458
Loc: Reno, Nevada
If there is 400 feet of loss on the way up, there is 400 feet of extra gain on the way up. There is also 400 feet of gain on the way down. 6,145 + 400 + 400 = 6,945 total gain for the round trip.

Edit: 6,500’ of total gain is a bunch. 7,000’ is even more. But when you stagger back to your car, the difference is what a former boss of mine would call “mouse nuts.” It just doesn’t matter.


Edited by bobpickering (10/15/19 07:01 PM)

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#56456 - 10/16/19 11:55 AM Re: Measured elevation gain/mileage MWT from the portal [Re: Kascadia]
Halfdomer Homer Offline


Registered: 04/07/16
Posts: 51
Loc: Los Angeles, CA
Yes 6900' is very close. Every time I have gone up there my GPS is close to that number given margin of error. Also, a little over 21 miles RT. Trail crest 200' back and forth, plus the ups and downs on the back 1.9 plus Bighorn park.

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#56496 - 10/25/19 11:09 PM Re: Measured elevation gain/mileage MWT from the portal [Re: Halfdomer Homer]
Jonathan C Offline


Registered: 03/03/19
Posts: 45
Loc: Los Angeles, CA
I've analyzed raw tracking data from gpx files from various devices on various hikes over the years. When you look at the raw data you quickly realize why there is so much difference in reported mileage and elevation gain between devices and even different apps on the same device/phone. The data is extremely noisy and needs to be filtered to separate the signal from the noise. Every device & app has slightly different filtering algorithms. The "true" number is typically impossible to know from GPS data alone. Routing apps (e.g. caltopo) can also be inexact due to accuracy issues in the underlying data they use to determine the route and elevation along the route.

Just click through the recordings of any popular trail on Alltrails and you'll see track after track with the exact same shape (not including alternate routes) but noticeably different mileages and elevations.

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#56497 - 10/26/19 09:57 AM Re: Measured elevation gain/mileage MWT from the portal [Re: Jonathan C]
bobpickering Online


Registered: 02/07/10
Posts: 458
Loc: Reno, Nevada
GPS tracks can be really noisy. The routes that CalTopo suggests when you add a line can also be noisy. Trails are often not where the maps and CalTopo say they are. The last few months, I’ve been zooming in with CalTopo’s Google Satellite layer and looking for where the trail actually is. But you can’t always see the trail. And sometimes there have been trail changes since the last satellite image. (Google Satellite doesn’t show the recent trail repair and re-routing on the Shepherd Pass trail.)

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#56503 - 10/28/19 02:34 AM Re: Measured elevation gain/mileage MWT from the portal [Re: bobpickering]
britonwhit(ney) Offline


Registered: 03/06/14
Posts: 81
Loc: UK
How much is it genuine noise, and how much is it the fact that you're trying to measure a fractal? It's like the coastline measurement problem, just in the z dimension - there is no right answer, any answer between the net gain of c. 6.2k ft, and infinity (which may explain why it feels further in descent!) are possible answers depending on the resolution chosen. The more accurate the underlying map, the greater the elevation change that will be recorded.

A perfectly accurate, infinite resolution altimeter would record an apparently "noisy" signal as it measured the up and down movement of the hiker it was attached to.

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#56504 - 10/28/19 11:35 AM Re: Measured elevation gain/mileage MWT from the portal [Re: Kascadia]
RichardK Offline


Registered: 11/06/09
Posts: 116
Loc: East Coast Florida
My GPS (a Garmin Montana 610t) will take a waypoint every 50 feet at the smallest increment that can be specified. If you overlay any GPS track on Google Earth where a trail is visible, you will readily see that small twists and turns in the trail are not recorded. GPS distances have this error.

GPS altitudes are not as accurate as lat/long measurements. Garmin has a brief discussion here. A more detailed discussion is here.

The elevation difference between the Whitney Summit (14505') and the Portal (8365') is 6140'. The drop from Trail Crest (13600') to the JMT (13482' per Topo!) is 118'.

So, a first pass number for total elevation gain on the round trip is:

6140' + 118' + 118' = 6376'.

I am not remembering any other up hill/down hill sections that come close to the drop from Trail Crest to the JMT. I know that there is a small drop getting into Bighorn, but it wasn't much. So, I think 6376' is a reasonable number. You could call it 6400'. If you want more accuracy than that, a surveying crew would have to measure the entire trail.


Edited by RichardK (10/28/19 11:45 AM)

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#56536 - 10/31/19 07:21 PM Re: Measured elevation gain/mileage MWT from the portal [Re: Kascadia]
Trail Lotus Offline


Registered: 09/22/19
Posts: 7
Loc: CA
I got 6,660 on AllTrails. Clean recording as a dayhike. In fact, that's a good place to go if you want to summarize what people are actually recording. Just make you're looking at recordings of people who do it in a single recording without any pauses from start to finish.

Here's mine: https://www.alltrails.com/explore/recording/mount-whitney-via-mount-whitney-trail--4393

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#56539 - 11/02/19 08:38 AM Re: Measured elevation gain/mileage MWT from the portal [Re: britonwhit(ney)]
Jonathan C Offline


Registered: 03/03/19
Posts: 45
Loc: Los Angeles, CA
Originally Posted By: britonwhit(ney)
How much is it genuine noise, and how much is it the fact that you're trying to measure a fractal? It's like the coastline measurement problem, just in the z dimension - there is no right answer, any answer between the net gain of c. 6.2k ft, and infinity (which may explain why it feels further in descent!) are possible answers depending on the resolution chosen. The more accurate the underlying map, the greater the elevation change that will be recorded.

A perfectly accurate, infinite resolution altimeter would record an apparently "noisy" signal as it measured the up and down movement of the hiker it was attached to.

Yeah, like I mentioned above, you can analyze gpx files yourself very easily. The fractal concept is fun to think about (I've had the same thought myself) but with typical GPS receivers (dunno about super high-end ones) the noise is really just noise.

Below is data from a ~4 mile hike in the Angeles National Forest that I manually extracted the numbers from the .gpx, loaded into a spreadsheet, and then ran two filtering passes on.

It's only when you get to the third image that the total accumulated elevation gain and loss matches expected numbers. The raw elevation gain/loss in the first image is 2x higher thanks to all the noise. i.e. if you sum up the delta between every sample it says I climbed ~4000 feet instead of what should be closer to 2000.

Intuitively speaking, the third picture feels the most accurate to what it was like to walk the trail. There was a little bit of noisy up and down but not nearly as much as in the second pic.




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