It's long bugged me that there isn't a good source for viewing and printing seamless USGS topo maps online. Terraserver and MyTopo both have great nationwide coverage, but the quality of their scans can suffer, especially at printed resolutions. Web-based map viewers also tend to fall short when it comes to things like datums, UTM grids, etc.

So, using the data available at http://atlas.ca.gov/quads/ and http://fsgeodata.fs.fed.us/, I went out and created a set of map layers for California. It was a real pain and I probably never would have started if I'd known what was involved, but the final quality is great. I also created a map viewer that lets you overlay a UTM grid, switch between WGS84 and NAD27, make full-page prints, draw routes and waypoints, and transfer data to/from a GPS. You can browse the map layers at http://caltopo.com/map.html, or sign in to create a saved map, which lets you create routes and share the data with others. A very basic user guide is at http://www.caltopo.com/about.html.

The obvious benefit is the ability to load a few tracks and print a map (I've mad some nice 20x30 PDFs that are going on my wall once they get printed), but I'd really like to see people use the site to create maps that they can share with others: local bike trails, backcountry ski routes, named cliffs at a climbing area, etc. You can share a saved map with others by giving them the url of the map page, although you can also make a map entirely private or give others write access. As an example, here's a map I created showing a loop hike for Price-Aggasiz in Desolation that I like taking people on (trails in black, scrambling in red):

http://caltopo.com/map?id=FF37706C

In addition to USGS topos, the USFS road maps are super useful for navigating the maze of logging road sometimes required to reach a trailhead, although they're a bit dated. For an example, compare this map of the road to Shasta's North Gate trailhead to the USGS topo: http://bit.ly/rJrYud

All of this originated from a project I've been working on to host web maps locally for Search & Rescue, and the code powering it is the same, with a few UI tweaks to hide the SAR-specific stuff. As a result, parts of the UI are klunkier than if I'd written it as a standalone map viewer. I'd also like to add some additional map layers (contour lines that you can overlay onto aerial images, current USFS roads from their shapefiles, historical topos from the 1800s), but I've spent a bunch of time getting this ready for public consumption and need to give the SAR part of the codebase some love for now. Suggestions, criticisms, etc. welcomed in the thread or through PM/Email.

I could stare at this for days! Thanks so much! Bookmarked.

I'm sincerely impressed. I can't wait to start using this. Wow.

Very cool! Thank you very much for the effort and great results!

hmmm now if there were some free topos online for other states

USGS maps are free to download for everywhere in the US (just enter a search and the grid will show up):

http://store.usgs.gov/b2c_usgs/usgs/maplocator/(xcm=r3standardpitrex_prd)/.do

JD

There's also libremap.org. The scans aren't as high-quality as the USGS site, but the flat list of quads by state can be easier to navigate than the USGS's interface.

I wanted to bump this for two reasons. The first is that I just put up a collection of topos from 1885-1915 that gives a pretty cool vision of the way the state used to be. They don't line up perfectly, which is partly because the maps are off and partly because I didn't do a perfect job correcting for the obscure datum the older maps were made on, but it's close enough.

SF Bay Area: http://caltopo.com/map.html#center=37.83419,-122.31766&zoom=11&base=1900%20(CA)
LA: http://caltopo.com/map.html#center=34.04128,-118.24448&zoom=11&base=1900%20(CA)
Yosemite State Park (?!):http://caltopo.com/map.html#center=37.73787,-119.59408&zoom=13&base=1900%20(CA)


The second reason is that I've made the site an official fundraiser for my SAR team, Bay Area Mountain Rescue. If you find yourself viewing/printing a lot of maps, please consider sending them a donation: http://bamru.info/caltopo

Edited to add links.

Wow!

Really great site. Definitely bookmarking this, definitely going to be using this. This is amazing. The old 1900 maps set is super cool.

Only one question, it looks like from this statement "CalTopo puts the number of additional map layers after the +" that you can add more than 1 extra layer? I can't get it to do that when I click the +1. What am I doing wrong? Also I can't delete that one layer either, just turn it to 0% or refresh page. Am I doing that wrong too?

mattyj wrote:Yosemite State Park (?!):http://caltopo.com/map.html#center=37.73787,-119.59408&zoom=13&base=1900%20(CA)

I've never seen a map that had the original 1864 state park boundaries on it from before it became a national park. Great stuff.

This is great! I like being able to switch back and forth from Sat to USGS Topo, plus being able to add markers, gps data, etc. and view on all the different maps available. Thanks for the links!

bigbuilder wrote:Only one question, it looks like from this statement "CalTopo puts the number of additional map layers after the +" that you can add more than 1 extra layer? I can't get it to do that when I click the +1. What am I doing wrong? Also I can't delete that one layer either, just turn it to 0% or refresh page. Am I doing that wrong too?

No; setting it to 0% is effectively the same as deleting it. The +1 should change back to + when you set it to 0%; if it's not, let me know what browser you're using. There's a bug I need to fix that causes the tiles to still get loaded in the background, but that's another issue . . .

The UI doesn't make 100% sense right now because I don't have any of what I call "transparent overlay" layers. These are mostly transparent layers with vector data like roads and trails, and they show up as checkboxes below the overlay dropdown. I have some local county trails set up this way for SAR, but I can't make the data public as it includes closed trails, illegal use trails, etc. I'm working on contour lines (to put over aerial images) and USFS/NPS roads and trails; when these are available, they'll show up as checkboxes.

I can easily change it to allow extra "normal" layers, but I've found that once you go beyond 2, it all starts becoming a white blur.

mattyj wrote:No; setting it to 0% is effectively the same as deleting it. The +1 should change back to + when you set it to 0%; if it's not, let me know what browser you're using. There's a bug I need to fix that causes the tiles to still get loaded in the background, but that's another issue . . .

Oh you're right, I just wasn't paying attention. When I set it to 0% the +1 turns back to a +. I'm not sure if the tiles were actually loading in the background, but I think that's why this was bothering me when I was messing with it yesterday. Could have just been an illusion, but it was seeming to go a bit slower once I added the second layer.

Re: the other mostly transparent layers, got it. I'm sure they will be really useful if you manage to sort out which ones you can make public.

That *is* a crapload of work. Thanks for going through all that.

If you are looking for seamless viewing of topo maps in the US, i suggest http://mapper.acme.com/. I am there all. the. time. You can also switch between Google Map steet, terrain, and various satellites.

ALSO!! although not seamless by any strech, the USGS *just* released all of their topos (like, ALL. every scale, every edition) for California and many other states. http://nationalmap.gov/historical/

out-freaking-standing.

i was looking at the old topos of yosemite, too. I love tracing Tioga Road to Tioga . . . and that's it! The northern Sierra passes are facinating too. I believe the original Carson Pass Road (SR 88) still has a trail over one short section of it. The Johnson Cutoff had become the preferred method (US 50).