This is one in a periodic series of articles looking at second cities — places to base a campaign in published settings other than such signature cities as Waterdeep, Greyhawk or Sharn.
City: Hardby (5,100)
Published setting: Greyhawk (Wizards of the Coast/TSR)
Why it’s a good choice:
Clearly, the City of Greyhawk is the heart of the Flanaess, which means many of the great adventuring sites are near to the Free City. Setting a campaign in Hardby puts the players in the same proximity to those classic locales — Star Cairn, Maure Castle, even Castle Greyhawk — as well as the classic Ghost Tower of the Inverness . Unlike Greyhawk, which sits on the Selitan River, Hardby is the gateway to Woolly Bay, which opens up a host of other opportunities — either seagoing (pirate) adventures or exploration of any cities and sites along the coast. And of course, archmage Rary the Traitor is out there somewhere in the Bright Desert — someone will have to deal with him sooner or later.
Mind your Ps and Qs
If your players are in need of a Miss Manners lesson in how to behave with civility toward women, or if you have an all-female adventuring party that’s tired of serving a series of tyrannical kings, then Hardby is uniquely suited. The city is ruled by women, the Gynarchy. Though in the wider scheme the Despotrix must bow her head to her masters in Greyhawk, within the city she still holds considerable power. Players who prefer the intrigue of politics as a backdrop should enjoy the rivalries and shifting alliances within the Gynarchy — which I think is very much akin to the scheming one finds among the White Tower of the Aes Sedai of the Wheel of Time  series of books.
One place you must visit
I’d suggest taking a pass on the Great Cranes (which is on every map) and have the players hit the outskirts and visit, instead, Minaryn Castle, home to the Throne Knight Messalina, a wizard and adviser to the despotrix. If she can’t get the players in trouble, er, directed toward adventure, no one can.
I’m partial to the map of Hardby that came in Domain of Greyhawk map pack as part of the accessory The Adventure Begins  (ISBN 0-7869-1249-9, Wizards of the Coast, 1998), because it’s mostly blank, allowing the DM to fill it out themselves. The city’s leading persons and many intrigues were detailed in Dungeon 109/Polyhedron 168  in Paul Looby’s article “Hardby: City of the Scorned.”