Keyword puzzle: Two words that relate to the title.
This is not your ordinary Sudoku puzzle. Not only is it made up of letters, there are two sets of double letters. You need to have each of the nine letters in the word "GEOCACHES" in each 3x3 square, row(across), and column(down). That means "E" and "C" will be used twice in each of those instances.
The you will need to consider (across and down):
A3D3 A4D1 A7D1 A2D5 A6D5
A3D7 A9D4 A7D8 A5D8 A3D5
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