Cities: Skylines

Cities: Skylines, developed by Colossal Order (the same people behind Cities in Motion) and published by Paradox Interactive, is a modern take on the classic city simulation.

Released on March 10, 2015, it has received overwhelmingly positive reception by players, who cite it as a proper, full-3D successor to SimCity 4, unlike the disappointment that was SimCity 5. While it lacks the difficulty of SC4 and is not graphically impressive by modern standards, it makes up for it with an abundance of other features, like enormous maps, free-form road placement, establishment of separate districts with their own set of ordinances and taxation levels, fully simulated water and sewage systems, and full modding support on Steam.

The game can be found here.