Why are there two Stop IDs for one rail station?
Each rail station has one Stop ID for each direction trains travel out of that station. For example, one station might have Stop ID #11 for the inbound platform and Stop ID #12 for the outbound platform. The concept is similar to the stops on opposite sides of the street having different IDs. This dual ID feature for rail stations allows you to skip a step by not having to request a specific direction.
