Oxfordshire is the most rural county in the South East. It has a population of around 635,500, over half of which lives in towns or villages of less than 10,000 people. Being at the heart of England, Oxfordshire is very well provisioned for transport, with excellent rail links to London, Birmingham and Manchester from Oxford station; and with Didcot serving as the junction of north-south and east-west rail services across the UK. East-West rail is also in construction and will see the connection of Oxford to Bedford, including improvements to the existing line between Oxford and Bicester, introducing a new service to London Marylebone. It will see the introduction of ‘Oxford Parkway’ station, and work between this and Bicester town station is due for completion in September 2015, and work between Oxford and Oxford Parkway due by spring 2016. The M40 runs through the north-east of the county, linking Banbury, Bicester and Oxford directly to London, Birmingham and the North. It meets the M25 London orbital motorway at its junction 16. The major north-south route through the county is the A34 dual carriageway. The A34 links the Midlands and the North with Southampton, crossing the M4 at junction 13. The A420 road provides a fast link to Swindon and the M4 at junction 15. The A40 is the major western route to Witney, Gloucester, Cheltenham and the M5. Oxfordshire also houses the Oxford-London Airport, and has excellent coach services linking Oxford to Heathrow and Gatwick airports.