It might've gone unnoticed, but Gamespy is dead. This means Civ3 multiplayer is dead as well. But 2k didn't give up on this beautiful yet old game, and implemented Steamworks for multiplayer support. This only works if you have a Steam version of Civ3, but apparently you can trade your cd key for a Steam key:
http://www.rockpapershotgun.com/2015...py-steamworks/
If only they had put this much effort in PTW...