When booking your travel, please bear in mind that the first lecture will start at 1pm on the 11th July and that the last lecture will end at 3pm on the 14th July.
The STFC have a website detailing traveling practicalities for Cosener’s House, 15-16 Abbey Close, Abingdon OX14 3JD, Oxfordshire, which is where the course will be held.
The nearest mainline train station with a regular service is Didcot Parkway. From here it is a short bus ride or taxi to Cosener’s House.
Abingdon, can also be reached via Oxford. From Oxford, busses X2 and X3 can be taken to reach Abingdon city center. A taxi from Oxford to Abingdon can also be taken, and will cost somewhere between £15-30.
The nearest Airport to Cosener’s House is London Heathrow. From here you can take a bus to Oxford, followed by a quick train ride to Didcot or direct bus to Abingdon. You can also take the Heathrow express to Paddington and then change for Didcot. If you are traveling in a group, you may find it cheaper and more convenient to organise an airport transfer/taxi. (I found prices from £142 return for 4 people when I looked online).
Gatwick Airport also has a (less regular) bus to Oxford. Birmingham Airport (Birmingham International station) has a more or less hourly train service to Oxford (which takes about an hour). Airport transfers from London Luton are only slightly more expensive than those for Heathrow.