This is a list of major puzzles published by Nikoli. Terms in parentheses are published English titles for the various puzzle types. Nikoli is also a village on the island of Lefkada, see Nikoli, Greece Nikoli (ニコリ) is a Japanese publisher that specializes in puzzles and is also the nickname of the quarterly magazine issued by the company (the full name being Puzzle Communication Nikoli). ...
The aim of the puzzle is to enter a numerical digit from 1 through 9 in each cell of a 9×9 grid made up of 3×3 subgrids (called "regions"), starting with various digits given in some cells (the "givens"); each row, column, and region must contain only one instance of each numeral.
The attraction of the puzzle is that the rules are simple, yet the line of reasoning required to solve the puzzle may be complex.
The puzzle was carved into a hillside in Chipping Sodbury, near Bristol, England, in view of the M4 motorway.