Terraforming Mars: Hellas & Elysium, the first expansion for Terraforming Mars, consists of a double-sided game board presenting two new areas of Mars:

Elysium takes players almost to the opposite side of Mars equator, with vast lowlands for oceans in the north and a dry, mineral-rich south. Place a tile on Olympus Mons, the highest peak in the solar system, to gain three free cards!

Hellas, the southern wild, includes Mars south pole and the enormous seven-hex Hellas crater that just begs to become a giant lake. Building around the pole gives you new placement bonuses in the form of heat and possibly even water.

Each of these maps consists of new sets of milestones and awards with relevance for that particular map. Place three tiles around the south pole to be a Polar Explorer, for example, or race to have the most estates beside water on Elysium!