OCDEM by Coach from London
The Oxford Bus Company operates a frequent service, (X90), from London Victoria to Oxford. The journey typically takes about 100 minutes but this can vary depending on the time of day, volume of traffic and state of the roads.
There are stops in central Headington and at Gipsy Lane, both about 15 minutes walk from the Churchill site.
Ideally, for both services, get off the coach at the stop announced "Headington shops" and walk down Lime Walk all the way to the end. Cross over Old Road at the traffic lights and you will be virtually at the entrance to the Churchill Hospital site.