OpenTTD

OpenTTD is an open‑source transport simulation that reproduces the gameplay of Transport Tycoon Deluxe while adding new features. Players build and manage networks of roads, railways, ships and aircraft to move passengers and cargo, aiming to grow profitable companies. The game supports both single‑player and multiplayer modes, and its community maintains a wiki with a manual, tips and modding resources.

The software runs on Linux, macOS and Windows, with optional support for other BSD systems, and can be installed from prebuilt packages, OS package managers, or by compiling from source. It requires separate graphics, sound and music data files, which are provided as free OpenGFX, OpenSFX and OpenMSX packages, or users may use the original Transport Tycoon Deluxe assets.

OpenTTD is released under GPL‑2.0, allowing free use, modification and redistribution without subscription or tier restrictions. The project is actively maintained, offering stable releases, nightly builds and a community‑driven ecosystem of add‑ons, translations and bug‑reporting channels.