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King County Thomas Guide Challenge

A cache by TeamIDFC Send Message to Owner Message this owner
Hidden : 3/8/2008
5 out of 5
1.5 out of 5

Size: Size: regular (regular)

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Geocache Description:

What is the King County Thomas Guide Challenge?

You’ve seen the DeLorme Challenge, the County Challenge, and perhaps the USGS Challenges – great caches that have taken cachers all over their respective states.  TeamIDFC has logged thousands of miles exploring all that our state (as well as Oregon) has to offer over many road-trips and many months.  In late 2007 Mr. IDFC first saw the San Bernardino Thomas Guide Challenge – a challenge cache that used the age-old Thomas Bros local street guides.  Intrigued at the chance to do more exploration of our local areas, TeamIDFC began planning a version for King County.

The Thomas Guides are street maps that were the de-facto local roadmaps and geographic breakdowns for many industries long before the prevalence of the GPS.  The Northwest Multiple Listing Service (for real estate) uses Thomas Guide pages and grids in every house listing, for example.  Thomas Guides are available online, in bookstores, and at Costco.

The goal of this cache is the same as the other challenge caches:  find a cache on each and almost every page of the 2008 version of the Thomas Guide that falls in King County.

King County

What’s so interesting about King County?

  • Population:  The 2010 census counted 1,931,249 residents, the largest county by population in Washington and the 14th largest in the United States. As of 2010,  we have a population larger than 14 other states, including Alaska, Idaho, and Montana.
  • History:  Founded out of territory from within Thurston County in 1852, the county was originally named for William Rufus King, the vice-president under Franklin Pierce.  The county was renamed after Reverend Dr Martin Luther King in 2005, and the logo changed to his image in 2006.
  • Geography:  King County has nearly twice the land area of the state of Rhode Island - 2,307 square miles. It is the 11th largest county in Washington (of 39) by area.  The highest point in the county is Mount Daniel at (7,959 feet) above sea level.  The county is home to two major and numerous minor lakes; 5 major rivers and untold creeks and streams; several mountains; and hundreds of square miles of national, state, and local parks
  • Geocaches:  At the time of this posting, King County had over 2500 caches!  Plenty of which you haven’t found!

Ok, what are the particular rules/guides/nuances of this challenge?

In order to claim this cache, you need to find a cache with a log in each available page of the guide. Those pages are:
474 475 476 477 478 479 504 505 506 507
508 509 534 535 536 537 538 539 564 565
566 567 568 569 594 595 596 597 598 599
600 623 624 625 626 627 628 629 630 653
654 655 656 657 658 659 660 661 682 683
684 685 686 687 688 712 713 714 715 716
717 718 719 743 744 745 746 747 748 749
774 775 776 777 778 779 807 808 837 838

Based on feedback from with other challenge caches and the forums, some clarifications:

1)  The posted coordinates are the actual coordinates.
2)  Page 742 is all private property on Vashon so it will not be included.
     2a) Page 837 only has a tiny portion of King County on it, and the only viable location for a cache is very poor, so we are removing it from the requirements.
     2b)  Update 6/18/14:  The sole cache for page 682 has gone missing so we are removing that page from the requirements.  Thanks for the owners keeping it alive as long as they did!
3)  Only physical cache types with a log count towards the challenge – no virtual,
        event, or Earthcaches will count for this challenge. Archived caches are eligible
        if properly logged before archival.

4)  If a Thomas Guide page includes space not located in King County only caches in the
        King County portion count. We will go off of the posted coordinates for a cache
        when determining in which county and page a given cache falls.

5)  The 2008 version will be considered definitive.
6)  When in doubt ask – they will be plenty of discussion but the final decision rests
        with the cache owner.

7)  The final cache is a medium lock-n-lock off a trail with .5 mile walk on existing trails
        – no bushwhacking required.

8)  Completed bookmark lists need to be posted before the final is attempted.

Thanks to Haicoole for starting the challenge phenomena; to Mount10Bike for the Washington DeLorme, the GPX filters, and the template for this page; and to Ms IDFC for putting up with Mr IDFC when he was obsessed with creating this challenge.

How do I participate and what tools are available?

If you wish to participate in the challenge please do the following:

1)  Create a bookmark list called "Your Name – [Fresh/Armchair] King County Thomas
        Guide Challenge"

2)  Make the bookmark list public and be sure to place this cache on it so that it shows
        up in the Book Marks lists shown on this cache page.

3)  As you complete each page, place ONE cache you are claiming for that page on your
        book mark list. 
Put the page number before the Cache Name on the bookmark list
        so that the Bookmark list becomes sorted by the Map Number.
    If you are not a premium member and cannot make bookmark lists please send a file containing your finds (GPX, XLS, or text in declining preference) to the cache owner and we will verify your completion for you.


    King County Thomas Guide Challenge


    A text file with the individual page outlines for use in filtering GSAK to show applicable caches.  v2 fixes errors to page 661. 


    A Microsoft Streets & Trips 2005 map with pins for the corners of each Thomas Guide page.  Very useful when used in conjunction with a GSAK export to S&T. Thanks to Hydnsek for creating the 2005 file.  Note:  This file works with newer versions as well.
    Challenge.gsk New 1/17/11: Hynr's Challenge macro (also great for DeLorme and County Challenges) now supports the King County Thomas Guide challenge.  Just download to GSAK and you can get an immediate tabular and Google Earth list of your found pages.

    Folks people have asked how to use the GSAK file.  Quick and dirty directions:

    1)  Choose Search/Filter (also Ctrl+F for a shortcut)
    2)  Choose the Arc/Ply Tab
    3)  Paste in the co-ords for a given page in the “Arc/Polygon points” text box
    4)  Choose the “Polygon” radio button
    5)  Hit go
      That will filter your database down to just the caches that are inside the boundaries that page.  If you've got your My Finds loaded you'll see your finds as well as any available caches.  Note:  The filters are for the entire page, so pages near the north, south, and east boundaries might contain caches that in Snohomish, Piece, or Island countries that are not eligible.
      Congratulations to the finishers!

      Rather than making hard and fast rules of “starting fresh” or not, we awarded two FTFs and two FTF prizes. Congrats to FunnyNose for his "armchair" FTF (that included the major task of placing caches in all the missing pages - way to go FunnyNose!) and to Valdes for his "fresh" FTF.  Our finishers to date:

      FunnyNose hydnsek BrodieBunch mc3cats CoolCowCachers
      Valdes SugarGliderSweatshop Aeolus The4Musketeers Jester
      rockitbiker JustMike lamoracke GravyMan wasillian
      Jaded Bolosky Scouting4Ever Prying Pandora WatchDOGSMike
      TeamIDFC rocketglider geodeez k7-wave BubbyC
      Almatheyounger Kiersolved Tobias & Petronella PhilNI crs98
      tomison masterpuzzler grossi benandjayme Muddy Teapot
      FrodoB CJJIT rakis2 Shaddow Frisky Biscuits
      Albert & Friends Terrible Ts vds TeamPoki crs98
      SleuthHounds FluCacher Curious Joe rambudo obarshay
      PNW_Native gsbarnes Douglas_Clan M&M KestrelAerie
      Peach&Pete Rock Chalk We R Here TrueRed06 BroncosFan4Life
      Sproutter Winos_Seattle

      Additional Hints (Decrypt)

      Urnq uvtu, 10 srrg bss genvy, pehk bs gerr

      Decryption Key


      (letter above equals below, and vice versa)



      188 Logged Visits

      Found it 61     Didn't find it 1     Write note 118     Publish Listing 1     Needs Maintenance 1     Owner Maintenance 3     Update Coordinates 3     

      View Logbook | View the Image Gallery of 27 images

      **Warning! Spoilers may be included in the descriptions or links.

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      Rendered From:Unknown
      Coordinates are in the WGS84 datum

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