This is a rewrite of the rules for using Oyster Prepay on National
Rail within the TfL area to show where it can't be used:

Chiltern Railways
---------------------
At Wembley Stadium, Sudbury & Harrow Road, Sudbury Hill Harrow and
Northolt Park.

Between South Ruislip and London Paddington

C2C
-----
Between Barking and Rainham.

First Great Western
------------------------
At London Paddington (Does not stop in the TfL area)

First Great Western Link
------------------------------
Between London Paddington and Greenford or West Drayton.

Gatwick Express
-------------------
At London Victoria (Does not stop in the TfL area)

GNER
-------
At London Kings Cross (Does not stop in the TfL area)

Heathrow Express
---------------------
Between London Paddington and Heathrow Central.

Midland Main Line
----------------------
At London St. Pancras. (Does not stop in the TfL area)

'one' Railway
---------------
At Bethnal Green, Cambridge Heath, London Fields, Hackney Downs,
Rectory Road, Stoke Newington, Stamford Hill, Clapton and Walthamstow
St James Street.

Between Seven Sisters and Enfield Town or Turkey Street.

Between Tottenham Hale and Enfield Lock.

Between Stratford and Upminster or Harold Wood

Scotrail
--------
At London Euston. (Does not stop in the TfL area)

Silverlink
-----------
At South Hampstead and Kilburn High Road.

Between Harrow & Wealdstone and Hatch End.

Between Gunnersbury and Stratford.

Between Canning Town and North Woolwich.

Between Gospel Oak and Barking.

Between Clapham Junction and Willesden Junction.

Southern
----------
Between Wembley Central or Victoria or Charing Cross and Cheam,
Belmont, Woodmansterne, Coulsdon South, Kenley, Riddlesdown or
Beckenham Junction.

South Eastern Trains
-------------------------
Between Victoria, Charing Cross, Elephant and Castle, or Cannon Street
and Coulsdon South, Hayes, Bromley North, Knockholt, St. Mary Cray,
Crayford, Barnehurst or Slade Green.

South West Trains
-----------------------
Between Waterloo and Feltham, Hampton, Hampton Court, Surbiton,
Chessington South or Stoneleigh.

Thameslink
-------------
Between Elstree & Borehamwood and Kentish Town.

Between Elephant & Castle and Sutton

Between London Bridge & East Croydon

WAGN
-------
Between Finsbury Park and Hadley Wood or Crews Hill.

Virgin Trains
---------------
Between Kensington Olympia and East Croydon.

At London Euston (Does not stop in the TfL area).