This is a VERY simple, VERY small example of a Fermat's Fences puzzle. To return to the Fermat's Fences page, click on the "End Animation" button. The animation will loop repeatedly, so don't worry if you miss something the first time through (or the 6th time...)

In this example, there are letters beneath the puzzle which indicate the appropriate comment below. The yellow boxes are highlighting where the deduction is being made on the playing board.

A) The starting position of the puzzle.
B) With no numbered posts on these two rows, all horizontal "rail possibilities" can be removed.
C) This 4-post in the bottom-left is the only numbered post that can reach the second cell from the top.
D) This 6-post must go left. IF it also went right two spaces, it would still have to go at least 3 cells down.
E) This 3-post is the only numbered post that can reach the cells immediately above and below it.
F) This 5-post must extend up to the 2nd row, as it's the only numbered post that can reach that cell.
G) This 3-post must extend down to the 4th row, as it's the only numbered post that can reach that cell.
H) This 4-post has no options but to extend downward 4 cells.
I) This 4-post has no options but to extend left and right as far as possible.
J) This 2-post is the only one that can reach the cell to its right.
K) This 2-post is the only one that can reach the cell at the bottom.
L) This 1-post can only extend to the right.
M) This 1-post is the only one that can extend to the cell at the top.
N) This 1-post is the only one that can extend to the final remaining cell.

Leaving us with the completed puzzle!