I’m talking where two holes run parallel but in a non-obvious routing.
Examples of obvious:
Any consecutive holes
1/9/10/18 and any combination therein.
Similar positioned holes within a nine like 3/12, 4/13, etc.
One that comes to mind is the Dueling Par-3 3rd and 10th Philly Cricket’s Wissahickon course.
Also, to prevent this simply being a listing thread explains why the unique or odd parallel holes exist and if it “works” in your opinion.