An early 19th C. wall hung Knife Sharpening Board.  This example being more unusally long and in original condition.
The board would have been laid flat and dampened.  Brick dust or grit would have been applied to the wet board and the knives were then drawn along it to sharpen them.
This is a nice piece of country kitchen decor and could be used to store utensils, candles etc.
 
Width 18 cm
Depth 16 cm
Height 120 cm