Oxford park and ride

[Northernlurker]

Staying with dd3 in oxford cowley premier inn after driving down from the north. I want to drive to a park and ride next day then spend the day in oxford before setting off for a to be determined destination east of oxford - visiting relative the next day.
Which would be best to use please? In oxford we want to look at a few colleges, maybe ashmolean and shop.

Either Redbridge or Thornhill park and ride from Cowley - both will take you into the city centre and you'll be able to walk to colleges/museum.

Thanks very much!

There are 5 P&R sites so my tip is to make sure you know which one you have used,all the bus stops in city centre are marked,but its not one bus serves all !
The sites are located off various A roads that surround Oxford