The caches can be of any type. Previous finds qualify, including caches now archived and events attended (even if you were the host), but not other caches that you placed yourself.
It is the published co-ordinates of caches, including Unknown/Mystery and Multi caches, that are used when determining which square a cache counts towards.
This cache is part of the Explorer Challenge series.
The grid squares on the Explorer 302 map "start" in the north west corner near Catterick Garrison at NZ 14000 00000 and "finish" in the south east near Thirsk at SE 44000 80000.
There are 600 grid squares and you need to find a cache in 127 of them to qualify. I set the challenge at 127 because that is the maximum number that a new cacher could find when the cache was published.
The Ordnance Survey grid reference is given on each cache page just below the main co-ordinates, as circled below on one of my other caches.
From July 2023 you must use the Project-GC Challenge checker https://project-gc.com/Challenges/GC5QM86/79251 to prove that you qualify.
If you don't currently qualify there is a GSAK macro that will identify the caches that will help you to qualify. You will need to run the macro with two databases in GSAK - your current finds ("My Finds" pocket query) and a pocket query centred on this cache and listing all caches you haven't found within 40 miles.
Any finds without proof of qualification will be deleted!
Have fun! The difficulty rating is for the challenge; the difficulty rating for the actual cache is 1.5.
You must sign the paper log in the cache to be able to log online as "Found". I reserve the right to delete your online log if you haven't signed the paper log in the cache.
When I set this cache in April 2015 I had found caches in 148 squares. By July 2023 I had found caches in 192 squares.