Mars Horizon is a simulation game that allows players to take control of a space agency, guiding it from the early stages of space exploration to the ambitious goal of landing astronauts on Mars. Players can create their own agency, complete with launch pads, research facilities, and astronaut training centers, while also managing the various challenges that arise during the space race. The game features turn-based missions where players must solve problems to gain scientific advancements and public support.

Additionally, Mars Horizon offers extensive customization options, allowing players to construct vehicles from a multitude of combinations and recreate historic missions from agencies like NASA and ESA. With a rich tech tree and the ability to either compete or collaborate with other agencies, players can chart their own unique path to Mars. The game also includes a Sandbox Mode for unlimited creative freedom in building and managing their space exploration endeavors.