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  1. #1
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    Comment on this Free California Topo map for Garmin GPS?

    I found this Free California 24k topo map, sounds like a better solution than the Garmin 10k topo map, has anyone used it yet?

    www.vr6.com/gps/map-dl.htm

  2. #2
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    I use and very much appreciate the vr6.com CA map. The contours are built from elevation data quantized at 40 foot intervals, yet are displayed at '20 foot resolution' due to interpolation of the data before building the IMG file. Although this adds some inaccuracy due to interpolation error, I find the extra elevation slices useful for hiking and biking offroad. It also contains water features and roads (at approx. the same density as the 100k U.S. TOPO 2008 map for the same area) yet the corresponding labels for these features are relatively sparse. For instance, the cities and highways located in the Bay Area are labeled, but individual streets are not.

    After biking with my unit for a few weeks, I have converged on using the Garmin TOPO 2008 dataset for road biking since roads, creeks, and other features are labeled. However the elevation slices in this dataset are quantized at 150 foot intervals, which often misses useful details for MTB.

    I'd like to merge the elevation data from the former dataset with the textual details from the latter, which would produce a seemingly optimal CA map for biking purposes. I've looked into this a bit, and concluded the best route is to compile publicly-available data into an 'optimal' CA .IMG file which could be shared without concern for Garmin copyright. I'll hopefully get around to this sometime, and will probably keep searching the web in the meantime to see if somebody else beats me to it.
    Last edited by ca_rider; 05-27-2008 at 02:26 AM.

  3. #3
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    I used the map from this source last weekend in Yosemite, great 20' topo information al around. The street/town/POI names are missing but I just add a bounch of waypoint myself. I do agree that if I roadbike I will get another map for the street names, for MTB this might just be fine. I would have to try out more on the riding trails to tell, but it looks great as far as the topo go.

  4. #4
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    Cool, I could have used a trip to Yosemite last week as well. I spent a few late hours looking into the compilation of an 'optimal' CA map derived from publicly-available data, and pretty much figured it out. I'll try to get that finished by the time I make it out myself in a few weeks I wonder why more DIY maps for Garmin aren't around-- sure some exist on the web, but the quantity is surprisingly limited.

  5. #5
    Its only 1" on the map!
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    This is a killer resource and I have been using it for quite some time. It is the only map to have in your Garmin if you ride trails in CA!

  6. #6
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    I don't know if anyone mentioned it but check out www.gpsfiledepot.com . There multiple states topo maps for free that are downloadable into mapsource so you can view them on you pc and gps it supports maps. The site has taken the CA topo map listed above and broken it down into smaller regions if you gps does not have a lot of memory.
    Check out the maps page. There are links on the top-right of the page for the free maps. Just follow the directions. It is really easy.
    As far as the original question, the map is awesome! It really is a big help when exploring unfamiliar territory.

  7. #7
    Its only 1" on the map!
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    Quote Originally Posted by bankerboy
    I don't know if anyone mentioned it but check out www.gpsfiledepot.com . There multiple states topo maps for free that are downloadable into mapsource so you can view them on you pc and gps it supports maps. The site has taken the CA topo map listed above and broken it down into smaller regions if you gps does not have a lot of memory.
    Check out the maps page. There are links on the top-right of the page for the free maps. Just follow the directions. It is really easy.
    As far as the original question, the map is awesome! It really is a big help when exploring unfamiliar territory.
    I was just checking them out this morning. I'm in the process of updating my GPS and TOPO how to section and came across it.

  8. #8
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    Yeah, its a nice find. It has the mtb vacation destination states (UT, CO, AZ) and links to other sites that offer both free topos and a few you need to pay for.

    If you are really into it, there are detailed instructions on how to create your own topo maps with free public data. That is way beyond my desires but, hey, everybodies boat floats differently.

    BTW, keep up the good work Bill. I have referenced your site more than once to prep for an outing or two.

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