1.
scavenger hunt
2. A type of puzzle in which you use a series of (often-vague) clues
to find an answer. Sometimes these lead to an actual treasure of sorts;
some old treasure maps are like this. Other times they lead to a token
prize, as in the MIT Mystery Hunt. In any case, usually at the end they'll
lead you to a certain location, and you'll know if you got there first
because the prize will still be there if you are. Often they will consist
of many different puzzles you have to solve and combine their answers to
get the final answer. Sometimes you'll have to go various places to pick up
parts of the treasure hunt as you solve it.
The puzzles of The Stone are done in treasure-hunt style, and they suggest
there's some big thing at the end.