If the tracks are at the same level as the entrance , this creates a disadvantage , as a side platform arrangement allows one platform to be adjacent to the entrance , .
An island platform means that both tracks have to be accessed by a bridge or subway .
If the tracks are at the same level as the entrance , this creates a disadvantage , as a side platform arrangement allows one platform to be adjacent to the entrance , whereas an island platform means that both tracks have to be accessed by a bridge or subway .