Cities of Splendor is a quartet of expansions for use with the Splendor base game. Each expansion is added to the basic game and they should be played separately.
The Cities replaces the noble tiles with 3 different city tiles (randomly taken from a pool of 14). The city tiles are objectives (in prestige points and/or development cards) and you need to fulfill one of them in order to win.
A copy of the base game is required to play.