Sunday, July 13, 2014

...And we're live!


A momentous day is upon us.

You--my dear friend--are witness to the inaugural post for the Sierra Mapper web application. 

Grab a cup of coffee, cozy up to your phone/tablet/computer, and let's chat a little bit about what Sierra Mapper is.

So what even is this thing? This "Sierra Mapper"?

Patience, dear reader. Like most bloggers, I'm going to tell you a long-winded, self-absorbed story to answer your simple question.

Like many great ideas, this one was born from some blurry amalgam of little pieces of things that I noticed were missing.

From seeing online forum-goers, wordily describing hiking routes in the Sierra Nevada to other forum goers:

"Yeah, head up Paradise Valley, but instead of crossing Wood's Creek, keep going north, and then maybe 1/4 mile before the Baxter Pass junction--that's the first main junction--..."

A highlighted map would communicate this far better. But where could one get a highlighted map?

From trying to plan routes in the Sierra--using spreadsheets, and Tom Harrison maps, and lots and lots of time. And still not being able to easily figure out elevation profiles. Looking in disdain at my DeLorme Topo 9.0 DVD--that should help with this--but it won't run on Linux, which is my OS of choice these days. Damnit. Why isn't there a web app that can do this?

From a lot of clicking in CalTopo:

"I can put my route in here, perfect!" 

" god, this is a lot of clicking"... click-click-clickclick.

How many people have already clicked this route in? How many have to before we find a better way?

The fix--for all those things--and more, is Sierra Mapper.

I still don't get it--what is Sierra Mapper? Some kind of web app?

I actually wasn't finished--I was pausing for dramatic effect.

But yes--it is some kind of web app.

The awesome kind, because it's free, and it's useful, and--while not perfect--does those things above.

An excerpt from the output of a route through Evolution Basin. Highlighted map on the left, beautifully labelled profile on the right. Well done, sir. Well done.

Okay, so how can I use it?

To get to the web app, just click on "Go to the Web App" below the banner on this very blog. Or navigate to  Once there, click on "Instructions" in the lower left for a brief run-down--I hope you find it is quite straightforward.

Is the web app finished?

Oh--oh no. No, no no. Absolutely not.

It is far--very far--from finished. It is a fawn, with knees-knocking--looking at the world with wide-eyed curiosity. It doesn't know what it will become, and the world doesn't know what to think of it yet.

And it's probably pretty buggy.

But it works well enough to share at this point, so I implore you, dear reader, to try it out.

And please leave me feedback--what works, what doesn't work, which trails you'd like to see added--where you'd like it to go from here.

You can contact me either by leaving a comment here, or by using the contact form to the right.

This is getting pretty long winded.

I have much more to say, but I will acquiesce, and defer it to later posts.

Now go forth, learned reader! Map routes and compare routes in the glorious Sierra Nevada with minimal clicking! And gaze in awe at beautiful profiles!


  1. Adam, great tool thanks for creating and sharing this!
    here are a couple ideas I had that would add to its usefulness:
    1. add in the locations of bear boxes, and (if possible) some sort of indication of where bearcans are required and where they are not.
    2. add a feature that would let you map out a multi-day trip from start to finish, and then split it up into any number of segments of equal mileage and/or elevation gain. i.e if you want to do a 5 day trip from A to B, it would divide it into 5 roughly equal segments for you to help you decide where to camp each night.


  2. Hi, Adam. I finally got a chance to use Sierra Mapper for real: went up to Mammoth and took a trip over Duck Pass Trail. I printed topo maps from caltopo, but also printed the profile from Sierra Mapper as it provided a really nice summary of the key points along the trail with the mileage and elevation profile between each point.

    I noticed in a couple places (maybe not that trail) that there were some useful "unnamed junctions" that coincided with high/low points along the route, elevation wise, etc. Cool. That was a feature I really wanted (and mentioned on BPL). Those don't seem to appear on the elevation profile, unfortunately.

    I'm still running into cases where the elevation gain/loss seems really off on trails that are ostensibly uphill/downhill all the way. For ecample, I'm thinking about going to Ediza Lk out of Agnew Meadows. Sierra Mapper says this is +2K' and -1K'. That's hard for me to believe since there is only one short bit of "downhill" on this route (dropping ~300').

    I looked at a couple of sections of the route I just hiked (Barney Lk to Duck Pass, Duck Pass down to the JMT). Each of those indicated about a 200' incline in the opposite direction (i.e., downhill going up to the pass, uphill descending from the pass). I know firsthand that that is a total exaggeration. I'm not sure there is *any( downhill heading up to Duck Pass!

    A couple more minor UI complaints:

    1. when I say Calculate Route, then hit Back, it forgets the zoom level I was at. This is a pain; maybe store that in a cookie or put it in the URL?
    2. The "Undo last" seems a bit wonky. Maybe just put a little "x" next to the list of points so one can selectively remove them?

    Bill Law

    1. Bill,

      Thanks, as always, for the feedback!

      In regard to the unnamed junctions--I've tried to judiciously label the meaningful local mins and maxes. If a node is labelled, it will appear on the profile. So if I've missed some, it's a simple fix--let me know which ones (if you right click on one of those unnamed ones that you'd like to appear on the elevation profile, it will tell you the node id--something like "k019", for example.) Let me know any of those offending nodes, and review them.

      In re: to spurious elevation change, yes, I agree, it is still a problem. Two sources dominate: error in the route location, and accumulated error from oversampling. I'm working on signal processing to help minimize error from the second source. It it's current incarnation, that signal processing reduces the elevation change on the Agnew Meadows to Edliza Lake trail from +1,938 ft / -962 ft to +1,581 ft / -585 ft--this seems closer to your experience. I hope to roll this out soon, and owe a blog post to it for more explanation.

      The same signal processing also decreased the elevation changes in the Barney Lake, Duck Pass, JMT section. I also hiked that trail last month, and I do recall a bit of downhill near Barney Lake. But it was small (probably < 100 ft). In any case, again, with the current incarnation of the signal processing scheme, the amount of descent I calculate going up to Duck Pass is only 118 ft, and the amount of ascent on the way down to the JMT is only 45 ft. Errors on the order of tens of feet per mile seem quite good, to me!

      Thanks for the UI suggestions. Yes, I have to look at how to better handle the "back" button. I'd like a "back" button that would take you back to where you left off, and a "start over" button that would function how the "back" button functions currently.

      The "undo last" is a little clunky. It was the easiest--but not best--implementation I could come up with. Your suggestion is more elegant and versatile (and probably intuitive).

      As you can probably tell from the lack of blog posts and updates, I haven't had much time to work on this lately. I'll probably have more time this winter, especially if we have another bad snow year.