A killer feature using this dataset would be an API to get ground-level elevation (above sea level) by passing a latitude and longitude pair. This exists in about 10 different APIs across the web already, but they're wildly expensive (or low-res). Google's is wrapped inside Maps for Business, which IIRC would cost far more than most startups can afford.
Of course, we can get the data "for free" from the USGS. But then we'd have to host and query the data ourselves, which becomes...expensive. I wonder if there's an inexpensive solution out there, for high-res elevation APIs?
See my above comment for a library that requires no geospatial database, just DEM files in gridfloat format. By recording information about each gridfloat file (bounding box, cellsize in lat/lng) you can do some simple math and only one disk operation (in the optimal case) to get an elevation value. Even with my crappy code in the library I mentioned in the other comment, the service is very fast on even spinning disks.
If you are interested in a service that does this, I host a redundant elevation service using NED, SRTM and ASTER data. It tries NED (highest res) first, falls back to SRTM and then finally to ASTER. ASTER is pretty bad in some areas, but it's the only dataset available above 60 degrees north/south.
Feel free to email me, cullen@ridewithgps.com if you want to use it, or just have questions about getting something together yourself.
Edited to add: code is open source, you just need an afternoon to tweak it (it's a ruby lib and a sinatra app) to work, along with some SRTM gridfloat dems. Code is here:
I'd also like to see a tile server that serves up (raw) elevation data rather than imagery. The tricky part is that elevation data has a sufficiently large dynamic range that you can't use most common image formats; but even with a custom tile format this would be useful for e.g. stereoscopic display.
I've been considering hosting one myself (based on USGS data), but only if it seems like there are other people who are interested in such a service.
Not to besmirch the USGS whom I think are great, but unfortunately they haven't had the funds to update these maps in DECADES and some of them are woefully out of date.
Yes, it seems hard to believe that a topo can go out of date, but features do change and in particular trails change.
Still, the fact that USGS has been making these available (on their own site and now this special one) has shown them to be the on the side of the good guys.
Perhaps, but they seem to be more up to date than the maps I bought from Garmin for my hiking GPS a few years ago. I bought the 2008 version of their 100k maps for the U.S., and found that Lake Nockamixon (1,450 acres) and Marsh Creek Reservoir (535 acres) were both shown as the tiny creeks that were present before they were dammed up to create the lakes in 1974 and 1973 respectively. Imagine that you are hiking along and encounter a lake that is a few miles long that is not supposed to be there. Those lakes are showing up just fine on the USGS site.
When I complained to Garmin, their response was that it was not an error and I should buy the (more expensive) 24k maps, which do show the lakes. They claimed the 100k maps don't have enough "detail" to show the lakes, yet they do show the tiny little creeks that were there 40 years ago, and they show other lakes that are only 22 acres. So, Garmin will happily sell you maps based on 40-year-old data and then charge you more to upgrade to newer data. By comparison, the USGS maps seem stunningly timely.
OpenStreetMap often lacks detail in the U.S. (it wouldn't be surprising for an area to have missing water bodies...), but maybe you are in an area where it is useful.
For what it's worth, the gtopo 24k product is pretty fantastic. Recently used the heck out of it on a 10 day hunting trip, it had a pretty ridiculous amount of roads not shown on any other detailed map.
One downside though is they are obviously using some elevation and image analysis to auto detect drainages and mark them as water. A significant number of draws in our area were marked as creeks, when it was actually an ATV trail along the bottom.
Other than that, a very very worthwhile product if you plan on doing any serious hiking/motorcycling/etc and plan on extensive use of GPS.
I definitely got bitten by this when I first started cross-country backpacking. I was following a ridge trail through the San Gabriel Mountains in Southern California when I came across a section that was overgrown with thorny bushes and completely impassible. The map I was using was merely two decades old (updated in 1991), but like you say, lots of things can change in 20 years. When I came back home, I looked up the reviews for that trail, and lo-and-behold, recent reviewers clearly described the trail conditions and explained possible alternative routes through the country-side. Definitely taught me a lesson: never rely on a single source of information (i.e. a map, even if it's commercial) when in the wilderness. Have pictures and written descriptions of important routes and milestones that you can cross-reference.
This is actually not entirely true. The USGS is on a similar schedule to the National Agricultural Imagery Program and releases new maps across almost the whole country on a 3 or 4 year rotation. These are digital maps with imagery in the background and computer generated contour lines. The only limitation is going to be the date on the elevation data.
They no longer look the same as old topo maps, but the serve the same function. If you look on store.usgs.gov you can find all of the current and old ones available for download for free.
This has been available for several years now, and is not new. In fact most regions of the country are on their second revision of these newer maps. The USGS actually has no choice but to give away the maps as they are publicly funded and required to give the public access. It is the same reason that we are able to download high res imagery over the entire country (the NAIP) for free.
http://caltopo.com is the most powerful, free online topo mapping software I know of. It essentially provides a google maps - like interface for navigating an array of different maps, including USGS. The print function is amazing.
CalTopo is awesome... that's who we get USGS maps from for gaiagps.com.
I can say with some pride that the reason CalTopo has nationwide coverage is because we made a deal with them a long time ago to get that done. Matt originally set up CalTopo for his search and rescue efforts in California, hence the name!
If you like historical maps as much as I do, this is pretty wonderful.
I'd always heard that there used to be a bunch of airports up and down the San Francisco Peninsula. Now I can see where they were: Bay Meadows, San Mateo, Belmont, Cooley (a private airport north of San Carlos), downtown Mountain View, and a seaplane base by the San Mateo Bridge:
And if you're around Palo Alto, did you know that Hawthorne Avenue, three blocks north of University, used to be a railroad spur leading to the Catholic University (now St. Patrick's Seminary)?
The quote sign is a legit character in a URL. That is, a valid URL can end with a quote sign character. I don't think ignoring it would be a good idea.
That's interesting. Before my previous reply I appended a quote sign in my browser's address bar (in this page) and pressed "enter", expecting it to turn into %22 in case it's not supposed to be there but the quote sign remained intact; that's why I posted my reply without checking the RFCs.
The tilde (~) is also invalid in a URL according to the RFC, but that doesn't stop everyone for using it for user names. I doubt your browser will escape that one either.
I don't think the commenting system is meant to process html. Perhaps it is a very loose regex of (http(s)?://.*)\s or whatever (sorry I didnt check to see thats valid!)
The Danish Geodata Agency (Geodatastyrelsen, abbr. GST) provide point clouds, elevation rasters (both ground and surface), topographic maps and more in a national project that started in 2011. http://eng.gst.dk/maps-topography/topographic-data/
As an experiment, they even have a couple Minecraft servers running with a copy of the elevation model in 1:1 (site is in Danish only): http://gst.dk/emner/frie-data/minecraft/
In New Zealand, LINZ (government mapping agency) provides all of their data online under a Creative Commons Attribution License: https://data.linz.govt.nz/
I love Gaia GPS, it's my primary GPS app. But the display has been annoyingly buggy for years (seemingly switching zoom levels randomly sometimes, drawing a line to a waypoint incorrectly after selecting "Guide me"). Map download regions can only be set to rectangles when few trails are that shape (e.g. any trail other than a straight N-S or E-W line will require downloading many extra tiles). In the map display, it impossible to hide the top row of buttons - I wish there was a simple gesture, like two-finger swipe up, to toggle display of all UI elements. That said it's still better than MotionX.
Thanks for your notes. Maybe you can send answers to support@gaiagps.com, but I have a couple of questions...
1) What version are you on, the latest iOS version we pushed, 9.1.3?
2) When you say it switches zooms randomly, is this just while looking at the screen, it jumps? Any other info?
3) You can also "Download Map Along Track" too - for any saved route or trail. We never considered polygonal downloads to be that useful, and also adds complexity to the UI. We'd do it, but it's not a priority, and we'd want to do it just right.
4) When the Guide Me line is wrong, in what way? Does it not end on the waypoint? Does it not start with where you are?
May I make a feature request? Under export track, there is one option, email. could you make a setting so I could set an email address and when I click email it goes out without further intervention? thanks.
That's pretty cool. I'm a casual user who might go on a hike a few times a year; thought about picking this up but $20 plus IAP (do I need to buy maps?)... is there a trial or lite version?
1) There are no additional map costs, which is one of the big differences between Gaia and a Garmin GPS.
2) No lite/trial version besides the website (but email for a refund anytime). There will probably be a free app along soon though, useful on its own, to help market the paid products.
3) As for Gaia's IAP (GaiaPro), we added that much later, so I would call it "optional."
> trails are not currently included as one of these layers—a significant drawback for hiking.
= (
Still, it's nice. But a lot of mapping/trail apps will probably still be charging you money to download topo maps, since it's a significant source of revenue. Topo maps have actually been available for free for a long time; it's just really god damn aggravating trying to put them on your device and load them into your program of choice. Plus, the new PDF format sounds incompatible with old apps.
The US Forest Service has GPS data for many trails. In 2013 I happened upon a USFS GIS server hosting that data. I began displaying that trail data with my Gmap4 browser app and asking questions so I understood the data better.
Then the trail data disappeared from the GIS server.
Apparently USFS management was clueless that anyone who (1) knew the address ("endpoint") for the GIS server and (2) had GIS client software, could display (gasp!) the trail data.
I have seen the trail data. Is it perfect? No, of course not - and it never will be. Is it more right than wrong? Absolutely!
Certainly the USFS could provide that data to the USGS so many more trails could be included on the new digital topos but so far the USFS has refused to do so.
Naturally I filed a FOIA for this trail data and naturally it was denied. My FOIA appeal is currently pending before the USFS Chief.
Here's a bit of good news. Before the trail data disappeared from the GIS server I downloaded the data for trails in the national forests in WA, OR and CA. I then processed that data with some custom code to make it more useful and produced a series of trail maps with mileages. If you are curious you can visit the Gmap4 examples page and look down just a bit for the link to the national forest maps.
http://www.mappingsupport.com/p/gmap4_examples.html
This is one of those "wow, that's amazing!" things about the internet. I used to save up my money as a kid to buy USGS quads. Naturally, I didn't have that many of them, and you could only find local ones, and not even all of those were always in stock. Now... it's all right there for free!
Being overly pedantic, there is more or less wide opposition to getting such data sets "into OpenStreetMap", it's better to treat it as a second data set at render time (as above).
Another useful site is http://viewer.nationalmap.gov/viewer/ which is a Google Maps like interface that allows downloading map data, topos, and other data files.
The Libre Map Project has a copy of the data (they were really hard to find for a while) and allows searching for feature names and downloading TIFFs of USGS quadrangles, TFW files, and TIGER files.
I had already downloaded USGS maps of my own town in 2012. The maps are quite up to date here, and based on beautiful aerial photography. But I upvoted this submission because the linked article includes the tip about how to enable USGS information in Google Earth, which is cool.
I have used http://www.mappingsupport.com/p/gmap4.html a few times on my phone to show my location on
high-res topographic maps. It works offline which is awesome for saving battery on a long trek
Thanks to timboslice for mentioning Gmap4. I am the developer of that browser app.
By my count there are 5 browser apps that I refer to as enhanced Google map viewers. Each of us devs have produced our own version of Google maps on steroids so you can surf maps (including seamless topos), display your data, or display other data that you find online.
In order more-or-less by launch date, these 5 apps are:
ACME Mapper
GPS Visualizer
Gmap4 (Joseph Elfelt - that’s me)
Hill Map
CalTopo (Matt Jacobs)
A few years ago the USGS made very hi-res scans of all (yup “all”) their paper topos. Matt shipped a box of harddrives to USGS and got back copies of those scans for the most recently published paper topo for all of the USA. Of course for some locations the “most recently published paper topo” is rather old. Matt whipped up some GDAL magic to de-collar those scans and chop them into tiles. He is hosting the tiles on Amazon’s cloud and invited me to display them with Gmap4 (where I call Matt’s tiles “t4 Topo High).
Finally here is a project I just started a few days ago to use Gmap4 to display data that (1) is hosted on state and federal GIS servers and (2) shows public land boundaries and recreation features. Here is the top page for this project. OK, time to ’fess up. I’m a software dev, not a web designer.
http://www.propertylinemaps.com/p/public_land_map.html
(The html pages for these public land maps contain a plug for my startup which georeferences land surveys and property legal descriptions.)
One of the next features I am going to add to Gmap4 is the ability to click a GIS feature and see a popup with the attributes for the thing you clicked.
Drawing a rough box on a map of the US I estimated about 40 degrees of longitude by 20 degrees of latitude. The most detailed maps are the 7.5-minute quadrangles, which I believe are available for nearly all of the continental US. Since 7.5 minutes is 1/8 of a degree, that gives 40208*8, or a bit more than 50,000 maps. A quick browse through the USGS site found this quote (http://store.usgs.gov/b2c_usgs/usgs/zproductinformation/%28x...): "It takes about 57,000 maps to cover the conterminous 48 States, Hawaii, and territories." They go on to mention that Alaska's most detailed coverage is the 15-minute quadrangle series. A similar estimate for the 15-minute coverage of Alaska is around 3000 maps, plus 1/4 of 57K (14K) for the 15-minute maps of the area already covered by the 7.5-minute series, plus a few thousand for the smaller-scale series (30x60 minutes, 1x2 degrees, index maps, etc.) So I'd guess somewhere around 75-85 thousand maps.
The majority of these maps were originally intended to be printed on 23x27 inch sheets of paper. Assuming they were printed at around 300 dpi, somewhere between 1-8 bits per pixel (after compression, this is the shakiest part of my estimate!), that's around 50 million pixels per sheet, somewhere around 6-50MB per sheet. So somewhere between 1/2TB to 4TB for the whole data set (and I could easily be too low or too high by a factor of 2).
Heh, looking at my neighborhood, the smallest available file is a scan of the 1933 7.5-minute Sierra Madre quad, 5.24MB, and the largest is the 1979 30x60 minute Los Angeles quad, 44.53MB. Most of the 7.5 minute quads seem to be in the 15-30MB range. So I don't feel so bad about my "shakey" estimate of individual map sizes!
A lot if you want the raw data. The 10-meter (also knows as 1/3 arcsecond) national elevation dataset is somewhere around 330GB in an unprojected form. There's also the 3-meter tiles for limited areas which take up 9 times as much storage.
However, it doesn't stop there. As part of the 3DEP (3D Elevation Program)[1], Lidar/IfSAR data is being collected across CONUS. One of the products that will be available (hopefully next year) is a 1-meter DEM, which should roughly be around 35TB (100 times as much data compared to 10-meter).
Assuming you mean the raw data, I would guess it's a few petabytes.
A while back I made a script to download NED elevation data from the USGS site. The files were elevation data for 1/3 arcsecond or 1 arcsecond squares and were available in a float format and/or ArcGIS. The files for a 1/3 arcsecond square in ArcGIS format were zipped up and came to ~320 Mb. The float format files are even larger. I don't remember exactly, but I think there are a few thousand of them for the entire United States.
And that was just NED elevation data, not feature data like roads and trails or lakes, or aerial imagery or topo quadrangles.
FWIW, the script is on GitHub, but doesn't work any more due to changes on the USGS website. It actually uses PyQt's webview to do the downloads because the download process used a ton of Javascript with callbacks and notifications because the data was in a tape library and had to be fetched and loaded before the download could begin.
Of course, we can get the data "for free" from the USGS. But then we'd have to host and query the data ourselves, which becomes...expensive. I wonder if there's an inexpensive solution out there, for high-res elevation APIs?