clue, clew, clou

Clue or clue means a hint, or a shred of evidence that might solve a puzzle or a crime--
I read the crossword puzzle clue, but I can't think of the answer.
The detective searched the scene of the crime again, hoping to find a clue.
He doesn't have a clue, does he?

Clou or clou ( rhymes with clue ) means a major point of interest--
When he passed through a new city, he asked if there was a clou he ought to visit.
When reading an unfamiliar work, it helps to have someone who can point out a clou you might have missed.

Clew or clew ( rhymes with clue ) means a ball or skein of yarn--
She wound the loose yarn into a neat clew.
The cat got hold of the clew, and unraveled it all over the room.

Now that you know that, you can say--
 "This guidebook doesn't offer a clue to any local clou, other than the large statue of a clew of yarn in the town square."

Note-- "clou" is also the French word for nail, meaning the sharp bit of metal hammered into wood.
Note # 2--"clew" is also the British spelling of "clue".
"Clew" also has a nautical meaning, having to do with types of sails and their rigging.
Note # 3--"clueless" ( one word ) describes someone who has no idea what's going on--
The cool kids all though he was clueless.
Not to be confused with "clue less" ( two words )--
The detective had one clue less when he realized that the hair he had found was his own.
One might also find a town with a "clou less" than another town, or a knitter who has a "clew less" of yarn.