I want to make a treasure hunt for my neices and nephews… help!?

I’ve done treasure hunts and scavenger hunts before for them, but I’m looking for some new creative ideas. They are ages 11, 10, 8, and 7
(2 boys and 2 girls.) Does anyone have any creative ideas for making a treasure hunt, OR any websites devoted to showing people how to create a kids’ treasure hunt? THANK YOU!
Jacob, thanks for the suggestion, but that is a classic treasure hunt. That’s what I always do with them. Its become a tradition that I make a treasure hunt for them every time they come to visit, so I want some new ideas if possible! Thank you again!