The North Leigh Roman Villa is an excellent English Heritage site. It makes a wonderful day trip from Oxford. Take the train to Hanborough, and then go by footpath miles. A great spot for a picnic on a nice day, and plenty of lovely scenery along the way.
The Alfred Jewel. On display in The Ashmolean Museum, Oxford. I was lucky enough to hold it. It was in my office for 5 minutes en route to packing for loan and someone started building scaffolding outside the room, like the plot of a bad heist movie.