During the course of the game, players must build and expand their transport infrastructure. The only infrastructure present on the map at the start of the game are roads within towns (as well as seas and rivers which ships can utilise). All other infrastructure—ports, stations, airports, rail, canals, locks, aqueducts and depots—must be built by players. The tools for building a rail network are particularly powerful, and players have access to many different signal types to build a complex and interconnected rail network.