Factorio Forums

I know you can put the tracks and have the trains go on the left but the signals will always be on the right, this isn't correct.

The correct way for trains is left hand traffic and the signals on the left, the way god intended https://en.wikipedia.org/wiki/Double-track_railway

How would the game know which direction train the signal was for if there wasn't a set standard?

The Factorio development team is (mostly) based out of the Czech Republic, although Wube Software itself is incorporated in the United Kingdom. The majority of Railways in the UK, France, Italy, and Western Europe use Left-Hand-Running (except Spain!?), although this is probably more attributable to George Stephenson and/or an Act of Parliament than any specific holy deity.

The former Czechoslovak Socialist Republic (defunct since 1989) was a satellite state of the Soviet Union, although they still used "Standard Gauge" (1435mm) preferred in Continental Europe - not the "Russian Gauge" (1520mm). The convention for German railways was therefore followed - Right-Hand-Running. This was most likely the source of the convention adopted in Factorio - it is what the Devs saw in their local environment, so it was emulated in-game.

When you do left hand in factorio, you have the signals on the inside. This allows for compact designs.