While searching something on Github I stumbled over the following repo: https://github.com/Softwarepark/exercises/blob/master/transport-tycoon.md
This is a set of Domain-Driven Design (DDD) exercises. They take place in the universe of the Transport Tycoon. It is a game "in which the player acts as an entrepreneur in control of a transport company, and can compete against rival companies to make as much profit as possible by transporting passengers and various goods by road, rail, sea and air."
If you want to learn about DDD, or practice your DDD skills this is a great way to start…