Vigenere Condundrum Mystery Cache
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Difficulty:
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Terrain:
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Size: 
(micro)
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There is absolutely nothing wrong with the coordinates above. I'm sure they would take you to a very nice location where you could enjoy God's creation. However, if you want to find this cache, I don't recommend going there; I recommend solving the puzzle instead.
Note: This cache is being published in conjunction with GC50ERV, The Miami Valley Caching Conundrum #2.
So, the Caesar cipher uses a simple numeric shift to encrypt alphabetic characters. A Caesar cipher with shift 3 would encrypt characters by adding 3 to each character, so that A becomes D, G becomes J, and Y becomes B (note the circular shift). Most cachers are familiar with ROT-13, which is simply a Caesar cipher with a shift of 13. In a simple Caesar cipher, all letters to be encrypted are shifted by the same amount.
A more advanced cipher varies the shifts applied to the text to be encrypted. For example, the first letter could be shifted 1, the second letter 2, etc. The Vigenere cipher uses an approach similar to this. In this cipher, an encryption key is chosen, and this key determines the shifts required to encrypt/decrypt the message. For example, assume "CACHE" is the key. First convert the letters into numbers using A=1, B=2, etc. So, the C in CACHE indicates a shift of 3 for the first letter of the message. The A indicates a shift of 1 for the 2nd letter of the message. Well, that works great if the message is only 5 characters long, but what do you do for longer messages? Simply repeat the sequence, so that the 6th letter again shifts 3, the 7th shifts 1, and so on. Got it? Quite simple, yes?
For this cache, you merely have to decode a message encoded with a Vigenere cipher. The message is encoded by subtracting the shifts; thus, you just add the shift back in to each character and voila, there will be the original message which contains the coords. Oh, one minor point: I guess you need a key. I could give you the key, but what fun would that be? To get the key, you will have to solve a Caesar cipher with a shift of ... well, I'm not going to tell you.
Here's the message containing the key, encrypted with a Caesar cipher. Hint: the key is 6 letters long.
FBKYVBVPZJNRZKWFIZKNRZKWFIZKTIPGKFKYZJKVOKZJALJKWZCCVI
Here's the message containing the coords, encrypted with a Vigenere cipher. Assume N39 and W084. Note: the encoded message is a single line which has been broken into two lines for readability.
CWSXUCQPURKHEWMOSTKCUOODCWSDEDFFURKQOIDDOZKIMWOYRBFSYXRTUSVW
VMJQNEQQNOYQLZUIUYBNPBRZKOJDAOBOPDUKBZPPUFOLPDUYBXMEYQLCSRAYAZFN
You can validate your puzzle solution with certitude.
Additional Hints
(No hints available.)