This is another cache in the Explorer Challenge series, originally conceived by PetersfieldPoodlePosse, and based upon British Ordnance Survey grid squares as depicted on Explorer maps.
To complete the challenge you need to find (or have found) a total of 289 different caches. I expect a number of you will already qualify - so who will be the first to find the cache?
What is the Explorer 289 Challenge?
The cache is called the Explorer 289 Challenge because each of the 289 different caches you need to have found to qualify must be in a different British Ordnance Survey 1 kilometre grid square as depicted on the Explorer 289 Leeds, Harrogate, Wetherby & Pontefract map.
The caches can be of any type, previous finds qualify (including those finds now archived and events attended (even if you were the host)), in fact, any cache other than those you have placed yourself can be counted.
The grids on the map "start" in the south west corner, to the west of Ossett SE 25000 20000
and "finishes" to the North East of Green Hammerton at SE 48000 60000, giving a possible forty squares (South to North) by twenty three squares (East to West) equalling 920 squares in total. However, the top section of the map does not have easting squares 25 through 28, reducing the total by 60 to 860 possible squares of which you need to find a cache in 289 different squares to qualify. I know that some of you concern yourself with whether cache owners qualify for their own challenges so rest assured that I do with 358 qualifying squares.
For the purposes of this challenge the published co-ordinates of all caches, including Unknown/Mystery and Multi caches are those that are to be used when determining which square a cache counts towards.
So how do I know which of the 860 grid squares on the OS map my cache find is in?
Well, the British OS Grid reference is given at the top of each cache page just below the main co-ordinates, as circled in red below. Or if you click on the streetmap.co.uk link in the "For online maps..." section of the cache page, this will show the location of the cache in its grid square on an OS map.
In the above example, the Grid reference is SE 58365 43212. This is the location to the nearest metre. So the 1 kilometre OS Grid square which it is located in will be SE 58 43.
For those of you that want automated help to plan (or prove) your finds a GSAK macro for the Explorer 289 Challenge can be downloaded from here which produces a web page of your finds and any unfound caches in your current GSAK database selection that count toward this cache.
Here is mine that I ran earlier.
When you have found the 289 caches, you need to provide proof of that fact to be eligible to claim a find on the cache; this can be via one of any number of different methods you may have available:-
1. List the 289 cache codes and names and the corresponding 1km grid square in your found log. e.g.
GC48R5E #RW1 And through it all SE 40 32 (or if you prefer, SE 40459 32234)
GC43DHY Ready Steady Go... SE 43 35 (or SE 43742 35664) etc
2. Create a public bookmark list
3. After the GSAK macro has run and displayed its output in your browser window, save the web page (as an .html file) and email it to me.
4. Attach the GSAK macro generated image to your log, add it to your profile, or email it to me.
5. Create a Spreadsheet grid of your finds and attach an image of it to your log.
The GSAK route is probably the easiest. If you're not familiar with GSAK and/or macros, BaSHful has very useful help page based around the Explorer 146 Challenge.
STOP PRESS, FEBRUARY 2015, some clever sausage has created a web based way of showing qualification, just by uploading your My Finds PQ, you can find it here http://www.cgtk.co.uk/geocaching/challenges/explorer?gc=GC4PZJC
Any finds without proof of qualification will of course be deleted! Have fun!
My thanks to PetersfieldPoodlePosse for producing the GSAK Macro and whoever completed the first page that I plagiarised wildly...
As is the norm with my listings, this will be premium only for three months. Once you have completed the challenge and signed the log, you may display this souvenir on your profile.
Copy this text into your profile page
<a href="http://coord.info/GC4PZJC"><img src="https://dl.dropboxusercontent.com/u/12580593/Explorer%20Challenge/Profile%20Badge.jpg" />