Days out from London, with tube

[buzzword]

This is a specific question leading to a more general question.

I'm travelling from the Shepherd's Bush area to Oxford and back on Sunday.

(All prices below are with Network Railcard.)

The fastest and most obvious route is H&C underground to Paddington (£2.20 on Oyster), day return to Oxford (£16.00), and underground (£2.20) back again; making a total of £20.40.

Several questions arise:

#1: Travellers from Oxford to London can get a one-day travelcard, including tube, for £18.95; but this isn't valid for travellers coming from London, right? Is this enforced?

#2: Same as #1, but what if I had a one-day travelcard from Islip (a minor stop just beyond Oxford)? It's the same price (£18.95) but presumably I could legally break the journey in Oxford, and neither station nor train staff would know that I was travelling in the "wrong" direction?

#3: The National Rail journey planner suggests a route starting from Shepherd's Bush rail station, via Willesden Junction, then Bakerloo line to Paddington, for just £17.70. This is considerably slower than just taking the H&C line, but it also uses the tube and the same train from Paddington to Oxford. If I buy this ticket from Shepherd's Bush rail station, can I walk straight to Shepherd's Bush Market or Wood Lane underground station and open the ticket gates there? Or could I even take the central line to White City, transfer to Wood Lane (on Oyster it would be a valid out-of-station interchange), and onto the H&C line?

#4: While trying to understand all this, I uncovered a further oddity. A ticket from London Bridge to Oxford costs £19.95; but a ticket from e.g. Deptford to Oxford, via London Bridge, costs just £17.70. Why?

#5: In general, what's the best way for a Londoner to take a day trip out of the city at the weekend? Assuming you have to start at a tube station, travel into the centre, and take a train out again. There are many places which have separate tube and train stations, but the tube offers the more convenient journey. (The aforementioned Shepherd's Bush, Putney / East Putney, Hounslow / Hounslow Central, Balham, West Hampstead, Hendon / Hendon Central, etc.)

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For completeness, I'm aware that there are cheaper train options from Shepherd's Bush to Oxford, involving either tube to Ealing Broadway and stopping service, or overground to Clapham Junction then South West Trains to Reading. These are out of scope as they are too slow.

 

[Paul Kelly]

Off-Peak Day Travelcard Zones 1-6: £5.90
Off-Peak Day Return Boundary Zone 6 to Oxford: £11.55

Total £17.45 - but you can't split this way on a weekday, as the Network Railcard minimum fare will get in the way.

 

[Romilly]

As regards the OP's #1 and #2, the travelcards are not valid for the Oxford/Islip to London outward journey once you have started the London to Oxford/Islip return journey. If the travelcard is clipped on the London to Oxford/Islip journey in a way which identifies the train the OP is on, it would then be possible for staff to tell that a subsequent London-bound journey is in fact an outward journey being undertaken after the return journey. Indeed, the fact that it has been already clipped at all could well arouse suspicion.

 

[Paul Kelly]

And as well as that, since all journeys from Islip to Oxford are operated by replacement bus services at the minute, it would indeed be noticeable if you ended up inside the barriers whilst breaking your journey from Islip to London.

 

[Romilly]

As regards the OP's #4, the £19.95 fare from London Bridge to Oxford is in fact a Zone U1*Londn to Oxford ticket, i.e. it is a ticket from any Zone 1 Underground station to Oxford, whilst the Deptford-Oxford ticket is a ticket between two National Rail stations with a cross-London transfer.