|Click on the picture to enlargenatify|
I'd use it lke this:
- Give the party information that the entrance to some underground cave complex or tomb or something, containing something they want, is behind a waterfall on the River of Certain Painful Death (or whichever river you prefer).
- Provide them with landmarks to look for so that they'll know when they're in more or less the right place.
- Allow them to struggle up-river through dense jungle for three or four weeks.
- Eventually, when you're getting bored with their suffering, tell them that they've spotted the landmarks they're looking for and have them start casting about for the waterfall.
- Show them the picture.
- Have a digital camera handy to capture their expressions.