To solve this puzzle and find the cache you’ll have to see
Stockholm city as a virtual chess board. By solving the following
chess problem, you'll find the cache in one of the 64 squares.
Let us first define the chess board. The given co-ordinates
point to a place in the eastern part of Södermalm and they
define square f2. In addition square a3, (on the island
‘Stora Essingen’), is at N59°19.406'
E017°59.591'. You see that squares aren't actual squares, but
points. The board is placed so that white plays directly from south
to north.
The pieces are set on board as follows.
WHITE: Ke5, Rd1, Re1, Bc1, Bf1, b5, d5, e6, g5, h3
BLACK: Kb6, Qa4, Nd6, c5, e7, g6
(King, Queen, Rook, Bishop, kNight and a1/a2/a3=pawns)
Black has to move and will checkmate in second move,
disregarding what is white's response to the first move. Your task
is to find what is black's first move. The cache is in the square
to where black will take his/her piece in that move.
The cache is easy to reach once you've figured out its location.
It contains chessmen.
Also check out the other caches in my game series:
Sudoku
Casino Royale
Texas Hold'em
Scrabble
If you go to Helsinki, try to solve the similar
Helsinki City Chesspuzzle