My group had to locate the hidden entrance to an abandoned Gnomish city.  They searched for two days before they found what they thought was the entrance.  It was the entrance…., to Kiddieland, the Gnomish equivalent of a modern funhouse for children.  Evil, nasty super-gremlins had infested the place and had warped much of the magic there to terrorize suckers, er, characters who found the way in.