You read the riddle and share information with others. People can guess and put their votes on certain locations.
Either you have a "winning team" that get to all the locations, or the first to complete a preset sequence wins.
Even more interesting is locating a certain "runaway" car. Which people describe and notify about its last seen location at certain points. The driver wonders what all the attention they're getting is about...-- pashute, Jan 13 2016random, halfbakery