"Salsa" is the Latin word for "salted" and in the Concordia: Salsa expansion for Concordia players will discover:

Two new maps: "Byzantium" and "Hispania"
Wooden pieces for a sixth commodity: salt
City tokens for additional salt cities
27 Forum Cards for new strategies to follow

The cards are all different can be acquired during the game and salt your game with new strategic challenges! Some cards have permanent effects others return to stack after using. Both the sixth commodity and the new cards can be played with the base game and the Britannia expansion as well thus giving even more variety.