The compass does NOT have a 180 degree error.

The east and west directions are NOT reversed.


With those facts established, let's explain why.

Unlike most modern compasses, the compass in Derail Valley does not feature a rotating face card, compass rose, or whatever else you prefer to call it. The markings on the face of the compass are static and cannot change position. The red end of the needle on the compass will always points to the north, and the black end therefore always points to the south. Unlike many other compasses in other videogames, the Derail Valley compass does NOT indicate the direction you are facing. It indicates which way is north, and you must orient yourself based off of that.

The compass needle will always point north (towards the top end of the map). In order to properly establish your cardinal directions when using the compass, you MUST rotate your body so that the needle is aligned with north on the compass card.

This is where the Derail Valley compass (and every real-world compass of this type ever made, of which there have been many) differs from a more modern compass with a rotating card: the compass in Derail Valley only points north. It does not give you any information whatsoever about the direction you are facing if the needle is not aligned with the "N" on the card.

It is a common mistake when using the compass to assume that the direction the needle is indicating on the card (relative to the direction you are facing, with "N" straight ahead of you) is the direction you are facing. For example, if the compass is held straight out in front of you and the needle points to the left (aligning with the "W" on the card), you must be facing west, right? No! THIS IS THE WRONG WAY TO READ THE COMPASS.


Instead, you must rotate yourself (the in-game player) so that the red end of the needle is aligned with the "N" on the card. This will establish which way is north without any errors or misreading, and is crucial for determining the other cardinal directions.

Once you have correctly established which way is north, determining the other directions is extremely simple. As you are already facing north by necessity of having to rotate the compass to line up the needle with the "N" on the card, the cardinal directions are as follows:

• North is directly ahead of you
  
• South is directly behind you
  
• East is directly to your right
  
• West is directly to your left

Once you have your bearings established (literally), you then can quickly deduce which way you need to go. If you know you need to go backwards and to the left of where you are currently standing (still facing north), you now know that to be southwest. If you know you need to go east, you now know that east is to your right.

To ensure that you are using the compass accurately, I recommend the following test:

Go to the Steel Mill. Hold the compass and look straight down at the ground, so you are using only the compass to navigate. Orient yourself to north and remember that as soon as you face anywhere other than north, the compass no longer correctly indicates the cardinal directions.

Walk northeast until you find a set of train tracks. Then, walk south until you encounter a fence. Teleport to the other side of the fence and continue south until you encounter another set of tracks. Stop and look up. You should now be in front of the maintenance shed and turntable (or at least near them; this isn't a super precise test). Congratulations, you have navigated successfully and proven that you know how to read the standard needle compass in Derail Valley.