By plane
While Oxford has an airport of its own at Kidlington,[ (http://www.oxfordairport.co.uk) it is used mainly for private and charter aircraft and has very few scheduled domestic or international flights; it is useful only if you fly your own plane, or are able to charter a small aircraft, though flights to and from Geneva are currently in operation in the summer with Air South West, who operates a flight to and from Guernsey. (http://www.airsouthwest.com) (http://www.oxfordairport....)
The nearest commercial airports to Oxford are those around London, to the south-east, or Birmingham, to the north, with most foreign travellers preferring the former.
Heathrow is certainly the closest major airport to Oxford, followed by Gatwick in terms of size and popularity. Road access from both Heathrow and Gatwick fastest is by M25 heading north and west respectively and then the M40 to Oxford's outskirts follow the signs.
Oxford Bus Company (http://www.oxfordbus.co.uk) runs several airport bus services to Oxford Gloucester Green bus station running in from Headington and up the High with several convenient stops: check web pages below:
between London Heathrow and Oxford (http://www.oxfordbus.co.u...), £23 single, £27 return, frequency: every twenty minutes 5AM-10AM and 2PM-7PM, less frequently at other times
between London Gatwick and Oxford (http://www.oxfordbus.co.u...), £22 single, £29 return, frequency: hourly 6AM-8PM, less frequently thereafter
National Express Bus Company runs airport bus services to Luton Airport and to Stansted Airport: (http://www.nationalexpress.com)
Birmingham Airport has few destinations as the London airports it still has quite a lot, but it is definitely the closest to Oxford in terms of public transport travel time. Birmingham International Airport has its own railway station, which is connected to the airport terminal building via the free AirRail Link cable car shuttle, taking 1-2 min. From the railway station, trains depart to Oxford every hour between 06:14 and 22:14 and take about an hour to get there. A non-advance, non-rail card single costs £25.50, a return £28.80 off-peak or £51 any time. You could do a lot cheaper by booking an advance ticket though but be careful as tickets are valid only on the booked train, so if your flight is late and you miss the train, you will have to buy another ticket.
By road
Oxford is linked to London, the capital of England, by the 50 mile 80 km south-eastern stretch of the M40 motorway depending on traffic, which can be heavy, the journey varies between 50-90 min. The north-western continuation of the M40 also conveniently links Oxford with England's second largest city, Birmingham, and the West Midlands.
Parking and access restrictions are very stringent in the narrow streets of central Oxford, policed both by wardens and by cameras, with heavy fines applicable. The council has also implemented circuitous and confusing one-way traffic systems, making it difficult to get around by car. Visitors driving to Oxford from the south have easy access to the Westgate multi-storey car park on Oxpens Road near the city centre, which is handy but expensive.
An alternative is to use one of the five municipal Park and Ride National Park and Ride Directory (http://www.parkandride.ne...) services which are located in the city outskirts on all sides of Oxford these are well signposted. They offer free parking and, on the park and ride bus, take about 12 minutes to reach the city centre. However £2 is charged for the return bus trip to the city centre. Forget about using the Thornhill Park and Ride on weekdays, it is invariably full.
By train
Wikitravel has a guide to Rail travel in the United Kingdom.
Oxford has a large railway station in the western part of the city immediately west of the city centre and south of Jericho. Fast First Great Western trains run to and from London Paddington every half an hour, taking about an hour to complete the journey. Commonly, these trains call at Reading, Slough for Windsor Castle, and Didcot Parkway though not all trains call at each of these stations. Tickets to London cost £20 off peak without a railcard and £40 at peak times without a railcard, although you can buy tickets for about £4 if you book in advance and online. There are also stopping services to London calling at a large number of stations, which run every hour and take about 90 min to complete the journey. First Great Western also runs approximately hourly trains on the Cotswold line to Worcester and also to Bicester.
Cross Country Trains also run through Oxford, mostly running to/from Manchester and Southampton. These trains run approximately half-hourly in both directions but stop at about 9PM. All of these trains stop at Reading going south, and Leamington Spa for Warwick and Warwick Castle, and Birmingham going north.
By bus
Frequent and comfortable coach services run from several convenient bus stops to Gloucester Green coach station in Oxford, normally starting at London's Victoria Station, running westwards via Marble Arch, Notting Hill and Shepherd's Bush and then onwards to Oxford. Stops in Oxford include beside others Thornhill Park and Ride station, Headington, Brookes University, St Clements, High Street Queens Lane which is best for daily visitors, as it it right in the middle of the majority of University Colleges and finally Gloucester Green, which is also well situated. Bus companies between London and Oxford include Oxford Tube (http://www.oxfordtube.com), Oxford Bus Company (http://www.oxfordbus.co.uk) and the low-cost Megabus (http://uk.megabus.com) which one must book in advance via the website or by phone. The service uses the infrastructure of the Oxford Tube.
Prices range between £10 and £13 for an adult day return ticket. It costs slightly more £20 for an adult return that lets you return at any point within three months) and the journey time is usually 100 min. The Oxford Tube and the Oxford Espress both cost the same and run very frequently. They take slightly different routes in London, so the place that you want to go to/from may influence where you board the coach. If you wish to travel late at night, only the Oxford Tube runs 24 hours a day: the Oxford Express stops services between 2.30AM and 6.30AM.
There are regular bus services between Oxford and London's Heathrow and Gatwick airports with The Airline. (http://www.oxfordbus.co.u...)
There is also an X5 bus between Oxford and Cambridge, taking approximately 3 h 20 min, as well as buses to Bicester and Banbury run by Stagecoach. There are also several coaches to other parts of the country that are run by National Express.