blackcap basin mileage discrepancy

[frozenintime]

hi there!

i'm wondering if anyone out there might be able to weigh in on discrepancies i'm finding in the mileage between portal lake and the junction with the trail to fleming, disappointment and hell for sure lakes.

tom harrison has this distance at 16.8 miles.
nat geo says 13.2.
caltopo and gaia both show around 13 as well.

i'd be inclined to believe the three sources that say 13, but tommy h is the more respected and ground truthed source of the bunch.

i ask because we are planning a long last day from portal back to courtwright. this measures ~20 miles in caltopo and others: long and probably a bit boring, but doable. 

harrison doesn't go far enough west to show a distance to the courtwright trailhead, but i'd guess it's more like 25 miles, which takes us from doable to brutal.

i realize this is pretty niche stuff... but this is a pretty niche website...

[SSSdave]

Went to caltopo using MapBuilder Hybrid and it clearly added up to 12.9 miles between Portal and the Hell For Sure Pass and Blackcap Trail junction. But from Portal to the non-high wheelbase standard Courtright trailhead is another 5.2+0.5=5.7 for a 18.6 total miles. In this era, those caltopo mileages are likely from GPS tracks. Reads like the TH 16.8 miles was to the trailhead before GPS measurements.

https://caltopo.com/map.html#ll=37.1089 ... z=14&b=mbh

[Wandering Daisy]

Well I can add another discrepancy. This is what I have from my Topo program. It is "map miles" drawn from the 7.5 minute map. From Portal Lake outlet:

2.8 First Half Moon tr jct
1.7 McGuire tr jct
0.9 Second Half Moon tr jct
2.1 Meadow Brook tr jct
3.2 Flemming Lake tr jct
10.7 miles

Continue out:

0.8 Post Coral Meadow
1.2 Long Meadow
1.4 Hobbler Lake jct
0.7 Chamberlain Cabin
1.8 Maxon Meadow ?? is this what FS calls the Trailhead?
0.8 TH on Google Earth it is called Dusy-Ershim OHV TH- the parking lot is here
6.7 miles

17.4 total out from Portal Lake

Do you think the Harrison miles is supposed to be the total from Portal Lake to Maxon Meadow?

[frozenintime]

tom harrison shows 16.8 from portal to the HFS trail junction and then another 2.4 from the HFS junction to long meadow, and nothing to the west of that. so he’s pretty clearly not showing mileage to the parking lot.

daisy, i’ll take your mileage in a heartbeat!

[Wandering Daisy]

Dave's 18.6 is probably more accurate if it was taken from GPS tracks.
If you do the trip late season, there may be no water from Post Coral Meadow to the TH. That was the case last year for me.

[frozenintime]

yeah, my caltopo mileage is from the same function in that app. anyway, weird how off harrison might be here.

[Love the Sierra]

I am so glad that you posted this because I also saw that discrepancy when I was researching my trip.

[agfhst]

I found another discrepancy on Harrison's Kings Canyon High Country map a few years ago. If you look at the trail from Crown Valley down into Tehipite Valley, there's a segment from Crown Valley southeast to the National Park boundary that Harrison's map says is 4.7 miles. The Nat Geo Kings Canyon Sequoia map gives 2.6 miles.

Our group of seven, hiking at about a 2 mph pace, finished that segment in about 1 1/2 hours. So the Nat Geo figure seems about right, and the Harrison number way off.

[frozenintime]

interesting. do we need to send a sternly worded email to thomas?...