As i have mentioned a few times, there were once several branch lines leaving the GWE mainline up until the 1960's. Some still survive and could be used as they are today and they are... West Ealing to Greenford Southall to Brentford Waste Transfer West Drayton to Colnbrook Slough to Windsor Central Maidenhead to Bourne End/Marlow Twyford to Henley on Thames A further set could be created to reflect the lines as the were, pre Beeching cuts as follows... Southall to Brentford Dock West Drayton to Staines West West Drayton to Uxbridge Vine Street Slough to Windsor Central (large station) Maidenhead to High Wycombe/Marlow Twyford to Henley on Thames (large station) These two books are a invaluable resource for learning more about the lines and their evolution.