The 2 main sizes of posters for train stations are 4 and 6 sheet sized posters. 4 sheet are 60 inch x 40 inch and 6 sheet 70 inch x 48 inch.
4 sheet offer great value when it comes to advertising on a train station and are usually in as good a location as the 6 sheet posters but are half the cost.
Focal Point would in most cases promote 4 sheet to their clients due to the great value for money. Please ask focal Point for details of poster availabilities at any train station of interest to you