Oxford to Cambridge Expressway
The Oxford to Cambridge Expressway is a proposed grade-separated dual carriageway between the A34 near Oxford and the A14 near Cambridge, via (or near) Milton Keynes. The proposal aims to establish this route by linking existing roads and building new ones. The case for its creation is examined in a Strategic Study for the Cambridge – Milton Keynes – Oxford corridor, published by National Infrastructure Commission in November 2016. The NIC sees the road as being of national strategic importance by providing an outer orbital route around London, linking Southampton, the M3, M4, M40, M1, A1, A14/M11 and Felixstowe. Alongside its report, the Commission sponsored a contest to encourage suggestions for how urban spaces may be developed along the proposed route.
The government states that the Cambridge – Milton Keynes – Oxford corridor is one of the most significant growth areas in the country. Local authorities within the corridor are planning for substantial job and housing growth to support the continued economic development of the region. However, there is currently poor east-west connectivity, resulting in Oxford and Cambridge having better connections to London than each other or to major settlements between. In his Budget speech Autumn 2017, Philip Hammond referred to the plan and declared it was the Government's intention "To create a dynamic new growth corridor for the 21st Century".
Route and costs
As of September 2018[update], most of the eastern half (A14 to M1) of the route already exists.[a] However, the route for the western half, from the A34 near Oxford to the A421 east of Milton Keynes, has yet to be decided. The National Infrastructure Commission (NIC) was instructed by Government to evaluate options in order to identify the spatial areas on which further detailed assessments, including further engineering studies, a Strategic Environmental Assessment (SEA) and a Habitats Regulation Assessment (HRA).
The three broad corridor options that were considered by the NIC are shown in outline form on page 39 of the Oxford to Cambridge Expressway Strategic Study: Stage 3 Report. These were a northerly corridor (the existing A421 corridor to the A43 then M40 and A34), a (new) central corridor parallel with East West Rail, and a new southern corridor along the A418 corridor, bypassing Aylesbury to the north, meeting the M40 at or near Junction 7 or 8. In August 2017 the engineering consultancy Jacobs was awarded a £15m contract to examine these options. All three broad corridors begin at M1 J13, where the expressway currently (2018) ends.
In addition, two alternative corridors are shown around Oxford, one to the north (which may or may not be the current A34 route through Botley, though the report notes the current air-quality issue there) and another to the south between the M40 at J7 or J8 and the A34 just north of Abingdon.
In September 2018, the Government announced selection of Option B (near East West Rail), though the options for connection to the A34 north or south of Oxford remain unclear. Although the broad corridor has been selected, no decision on the route of the Expressway will be made until summer 2019 following a full environmental and ecological impact assessment.
Early estimates of the cost of completing the expressway are in the region of £3 billion.
In April 2018, Oxfordshire County Council submitted its preliminary response to Highways England.  Stakeholder consultations with local authorities, environmental and ecological groups, and residents associations were held throughout 2018. A wider public consultation on the route options are planned for 2019 and 2020.
New Towns along the route
In an interview in The Sunday Times in March 2018, Sajid Javid, the housing secretary, said that he would give the go-ahead to at least two new towns along the corridor "in the next few weeks" and could push for up to three more. As of 25 March 2019[update], these announcements had not materialised.
Development of land adjacent to Expressway
The National Infrastructure Commission launched a two-stage ideas contest in June 2017 in support of the project with the objective of encouraging a wide range of bodies to put forward suggestions about how the urban space alongside the route could be used.  In December 2017, the Commission announced that the winning submission was that proposed by Tibbalds Planning and Urban Design, The proposal is based on cycle and pedestrian transport and the worked example suggests a cluster of villages around Winslow, Buckinghamshire, which is on the East West Rail Link rather than the Expressway (though probably easily accessible from it).
On Tuesday 12 December 2017, Councillors at Oxfordshire County Council debated a Motion criticising the process by which Highways England will select a route with no opportunity for members of the public or their representatives to comment on the need for the road or the local impact of any particular proposed route. The Motion called for a Public Enquiry into the proposal, so that everyone involved has the opportunity to have their views properly taken into account. The Motion was carried by 49 votes to 5, with 1 abstention. On Tuesday 2 April 2019 the Council passed a further motion demanding that a fuller consultation is carried out asking local residents if they want an Expressway and associated construction before any route is considered. 
Keith Taylor, a Green MEP for the South East, said the lack of a potential public consultation of the proposed road breaches international environmental law. He made further criticisms after visiting Oxford.
On 3 October 2018 the Oxfordshire Growth Board wrote to Government demanding clarity with regard to the choice of route and funding. 
- "Oxford to Cambridge expressway strategic study: stage 3 report" (PDF). UK Department for Transport. 28 November 2016. Retrieved 3 August 2017.
- Autumn Budget 2017: Philip Hammond's speech 22 November 2017 HM Treasury and The Rt Hon Philip Hammond MP
- "Route unveiled for major new road and junction at Black Cat". Highways England. 18 February 2019. Retrieved 19 February 2019.
- "Jacobs wins £15m Oxbridge expressway contract". Highways Magazine. Retrieved 3 August 2017.
- Corridor announced to unlock full potential of England's economic heartland. Corridor B chosen for the Oxford to Cambridge Expressway. Department of Transport, 12 September 2018
- "Cambridge to Oxford road 'may cost £3.5bn'". BBC. 30 November 2016. Retrieved 3 August 2017.
- "County council's first thoughts on Oxbridge Expressway". County council’s first thoughts on Oxbridge Expressway.
- "Sajid Javid exclusive interview: Garden towns and expressway to sprout up in Oxbridge corridor". 4 March 2018 – via www.thetimes.co.uk.
- "The Cambridge to Oxford Connection: Ideas Competition". Competitions.malcolmreading.co.uk. Retrieved 3 August 2017.
- National Infrastructure Commission announces winner of Cambridge to Oxford Connection: Ideas Competition National Infrastructure Commission, 6 December 2017
- Winner: Tibbalds Planning and Urban Design: With Mikhail Riches, Featherstone Young, Marko and Placemakers, Expedition Engineering & Khaa National Infrastructure Commission, 6 December 2017
- Agenda and decisions; County Council; Item 15 Oxfordshire County Council, Tuesday, 12 December 2017
- Oxfordshire County Council, 01865 792422 (2 April 2019). "Agenda for County Council on Tuesday, 2 April 2019, 10.30 am". mycouncil.oxfordshire.gov.uk.
- Oliver, Matt (18 February 2017). "New £3.5bn Oxford-Cambridge Expressway route could pass through protected Green Belt". Oxford Mail.
- Briant, Nathan (26 October 2017). "Campaigners demand a say over controversial route for new Oxford Cambridge Expressway". The Oxford Times.
- "Campaign calls for new £3bn expressway to stay away from land south of Oxford". Oxford Mail.
- "This new £3.5bn road will slice through Oxfordshire - but will you get a say on the route?". Oxford Mail.
- "'Do we even need a new expressway to Cambridge?' asks MEP". Oxford Mail.
- Monbiot, George (22 August 2018). "This disastrous new project will change the face of Britain, yet no debate is allowed - George Monbiot" – via www.theguardian.com.
- "'A monumental disaster': politicians and campaigners lay waste to Government's £3.5bn expressway route plan". Oxford Mail.
- "More clarity on Oxford to Cambridge Expressway required". Oxfordshire Growth Board. 3 October 2018.
- Designated as the A428 from the A14 to the A1 and the A421 from the A1 to the M1. Apart from an approximately 10 miles (16 km) section between Caxton Gibbet and the A1, the A428 is already to expressway standard. The A421 between the A1 and the M1 at J13 is also to this standard. On 18 February 2019, Highways England announced final route selection to replace the single-carriageway section from Caxton Gibbet to the A1, with construction to begin in 2022.