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Current unsolved real-world puzzle

15
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1answer
684 views

MIT 1995 Puzzle Hunt: Unsolved “Connecticut Suite” Puzzle

Many of the solutions to the 1995 MIT Puzzle Hunt have been lost. Several groups have been able to solve most of them, but #23 Connecticut Suite remains elusive. Here is a reproduction of the puzzle....
3
votes
2answers
456 views

The Fenn Treasure Hunt (REAL!)

I heard of this riddle and wanted to pass it on to see if you expert puzzlers could solve it! These are clues for real treasure hidden somewhere in the Rocky Mountains. As I have gone alone in ...
1
vote
1answer
90 views

Bishop Wilberforce's Unsolved Riddle

Thought you guys might enjoy this -- an unsolved riddle from the 1800s. Story and contents of puzzle have been copy pasted from here: Bishop Samuel (“Soapy Sam”) Wilberforce, who once famously ...
5
votes
0answers
475 views

Need help with a cipher

I am trying to figure out a cipher I think I found in a book from 1982 and it's a 36 year old mystery we are trying to solve (I will reveal the book if this turns out to be something so everyone can ...
22
votes
6answers
11k views

The 10,958 Problem

Here is the task: Write down 10958 using all 1-9 digits in ascending order and only one time. You are allowed to: 1) group digits into numbers 2) use 5 basic operations: + - * / ^ ("^" ...
20
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1answer
2k views

Ricky McCormick's Notes

On June 30 1999, Ricky McCormick was found dead in an isolated area, 15 miles away from his home. He didn't own a car, and the area was not subjected to public transport so it is a mystery how he got ...
26
votes
4answers
2k views

This image contains a “Great Discovery”

The Puzzle: Source material taken from here As discussed on Numberphile, here is John Herschel's doodle, sent to his friend Charles Babbage. John H. John Herschel was an English polymath, ...
43
votes
1answer
4k views

Unsolved Mysteries: D'Agapeyeff cipher

The D'Agapeyeff cipher is an as-yet unbroken cipher that appears in the first edition of "Codes and Ciphers", an elementary book on cryptography published by the cryptographer Alexander D'Agapeyeff in ...
57
votes
1answer
8k views

Unsolved Mysteries: Kryptos

This is the second in a series of Unsolved Mysteries posts. These posts explore current unsolved real-world puzzles. Since these have been unsolved for years, it's uncertain whether anyone on on ...
16
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0answers
5k views

The Beale Papers

The background to this one's given here: http://www.damninteresting.com/89-263-201-500-337-480/ NB: These may not be a genuine cryptograms (current thinking is that these are gibberish); but I though ...
25
votes
3answers
2k views

Unsolved Mysteries: Magic Square of Squares

This is the first in what will hopefully be a series of Unsolved Mysteries posts. Note that this puzzle has no known solution, nor any proof that a solution is impossible. We will see how ...
71
votes
2answers
3k views

A good puzzle is a double-edged sword

A rare double-edged sword is currently on loan from the British Museum to the Magna Carta exhibition. The sword itself is described as likely made in Germany around 1250-1330 and includes the ...
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4answers
1k views

The 2 million, er, 20 dollar problem

Alfred is a guy who really likes solid shapes. He also really likes to keep his money in his wallet. What makes him the happiest? Getting a boxful of shapes at the Cheap Solids Store! The store has ...