Smarter Cambridge Transport
Girton Interchange

A14 Girton Interchange – a critical link

Updated July 2021 with a new design for an all-ways interchange and a multifunction transport hub.

Smarter Cambridge Transport updated proposal

The Girton Interchange was redesigned as part of the A14 Improvement Scheme, but this added no new connections. The two key objectives for our proposal are:

  1. Connect the A428 directly to the M11 in both directions, taking through-traffic off the heavily congested A1303 (Madingley Hill).
  2. Provide a new transport hub at the Girton Interchange, accessible from the A14, M11 and A428, with a visitor transfer hub, coach station, freight distribution/consolidation centre, exhibition hall and conference centre.

This rough sketch shows how these objectives could be met, mainly using land that is isolated by existing roads, and preserving or enhancing foot/cycle/bridleways:

Girton Interchange
Illustrative example of how additional road connections and a transport hub could be added to the Girton Interchange

View map interactively

New road links are shown in cyan, connecting with the new A1307 built as part of the A14 Improvement Scheme. Green dashed lines indicate realigned foot/cycle/bridleways and farm access tracks. Dark blue indicates a new bridge.

Transport hub

The Girton Interchange is a cross-roads of the M11 (from London), the A14 (the Midlands, Ipswich and the port of Felixstowe), and the A428 (Beford, Milton Keynes and Northampton). It is therefore an ideal location for a transport hub for people and freight.

Light rail link

A light rail line between the Girton Interchange, West Cambridge, the city centre, Cambridge railway station and the Biomedical Campus would provide the fastest and most reliable journey times to these destinations, making the Girton Interchange one of the main gateways into the city (the others being Cambridge, Cambridge North and Cambridge South railway stations).

Coach station

A coach station at the Girton Interchange will greatly shorten journey times. Coaches would not have to travel in and out of the city centre, which can take up to an hour at peak times. The light rail link will provide a fast and convenient way to travel between the coach station and key destinations in the city, with onward connections by bus or rail possible at each stop on the light rail line.

Visitor transfer hub

Car parking at the Girton Interchange would serve people arriving by car or private coach from outside the area covered by local transport. This would include tourists and visitors from all across the country. Parking would be charged at a level to deter local residents using it for commuting and shopping (to incentivise them to use public transport and local delivery services instead). The price charged per day would include a pass for unlimited travel on local bus and rail services.

Logistics hub

A logistics hub at the Girton Interchange would allow the transfer of freight between heavy goods vehicles running on the motorway and dual carriageways, and smaller electric vehicles running on local roads. Electric lorries and vans would transfer goods between the main hub at the Girton Interchange and smaller depots around the city. Last-mile deliveries could then be made from those depots by electric vans and cargo bikes.

Exhibition hall and conference centre

The Girton Interchange could be an ideal location for a large exhibition and events hall and conference centre. Public transport access from London, Stansted Airport and anywhere on the national rail network would be via Cambridge station and the light rail link. Coach services would also provide access from many major cities.

Comparison of connectivity

Significance of cell colours

  • Red: detour required to make the connection
  • Orange: dangerous or congested connection
  • Yellow: sub-optimal connection for a trunk road
  • Green: good connection
  • A1307 new:

Roads & junctions

  • A1307 city: Huntingdon Road
  • A1307 new: new local access road to Oakington Road
  • Jn 29: Bar Hill interchange (8.8km / 5.5mi detour from Girton Interchange)
  • Jn 30: Oakington Rd interchange (to be removed)
  • Jn 32: Histon interchange (5.6km / 3.5mi detour from Girton Interchange)

Ease of access to a Park & Ride at the Girton Interchange can be judged from the ease of access to and from the A1307.

Current connections

FromTo A14 west A14 east M11 A428 A1307
A14 west 2 roundabouts via Jn 32
A14 east via Jn 29 via Jn 29
M11 via loop via Jn 29 via A1303 via Jn 29
A428 via Madingley via A1303 via Jn 32 via A1303
A1307 via Jn 29 via Jn 29 via Madingley

Smarter Cambridge Transport proposal

The transport hub is accessed from the A1307

FromTo A14 west A14 east M11 A428 A1307*
A14 west 2 roundabouts 5 roundabouts
A14 east
M11 2 roundabouts

*The transport hub (coach and visitor transfer station, logistics hub, etc) is accessed from the A1307.

The M11–A1303 junction

Why doesn’t the M11 have slip ramps on the north side of the A1303? On the face of it, this would be a sensible addition that would improve access to north-west Cambridge.

Unfortunately there is a sound safety argument against adding slip ramps here: the distance between this junction and the Girton Interchange is too short for drivers joining and leaving the M11 to switch lanes safely. This is known as the ‘weaving length’, and is illustrated in the diagram below.

Illustration of weaving length
Weaving length between an on-ramp and the next off-ramp

The Design Manual for Roads and Bridges (Volume 6, section 2, part 1, paragraphs 4.34–36) sets a minimum weaving distance of 2km for rural motorways, and 1km for dual carriageways (‘rural all-purpose roads’). On this section of the M11, the distance would be about 770m, which is well below the minimum required.

If you examine other junctions on the M11 and A14, you will see that some are closer together than current minimum standards allow. This contributes to the poor safety record on these roads.

Possible future connections proposed by Highways England

At the time of the development of the A14 Improvement Scheme, Highways England responded to representations by Coton Parish Council with a possible future layout that includes additional connections (see pages 21–22 of Report 5: Design and Engineering standards). This would connect the A428 and M11 (via two roundabouts eastbound), but the A1307 would still not be accessible from the A14 east or M11; nor would you be able to get back onto the A428 westbound from the A14 west or A1307.

Girton Interchange possible future layout
Possible future layout at Girton Interchange proposed by Highways England

Another option considered by Highways England is to build a new link road from the A428 at the Madingley Mulch roundabout to the M11 at the Barton Interchange (see page 25 of Report 5: Design and Engineering standards). This would meet very serious objections on environmental grounds, and would not provide access to a transport hub at the Girton Interchange. A Park & Ride at the Madingley Mulch roundabout has already been rejected as part of the Cambourne–Cambridge scheme because of its environmental impacts.

Highways England suggestion for how to link A428 and M11
Highways England suggestion for how to link A428 and M11

The previous version of this page, which included commentary of the A14 Improvement Scheme is available in the archive.

Edward Leigh

Edward Leigh is the leader of Smarter Cambridge Transport, chair and independent co-opted member of the Cambridgeshire Police and Crime Panel, chair of the South Petersfield Residents Association, business owner, consultant, and occasional blogger about making the world and Cambridge a better place to live.


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  • Confused as to whether or not there are current or future consideration to giving a slip road from M11 southbound to A1303? Currently traffic has to leave the A14 at Histon junction and travel in to Cambridge then along Madingley Road, or leave A14 later, down M11 a considerable way, before doubling back and heading North up M11 to leave at the northbound sliproad. Adds time to the journey and increases congestion in Cambridge. Any plans to improve this?

    • Though this would improve connectivity, for safety reasons Highways England won’t add new M11 on/off ramps on the north side of the A1303. I’ve added a section near the bottom of this page explaining why.

  • Hi,

    Being a Cambourne resident who commutes to London every weekday and therefore has to endure the congestion on Madingley Rise every time, the idea of no direct connection from the A428 to the M11 is frankly pathetic, there always a way of achieving something if you want to, the problem is we have the usual ‘experts’ who for reasons of their own aren’t interested in sorting out an issue that isn’t directly connected to building the new A14, the fact that this is an obvious thing to do and an obvious time to do it doesn’t concern them.
    There clearly isn’t any joined up thinking as in addition to the above stupidity the route of the new East West Railway from Oxford to Cambridge enters the city from the south west having traversed lightly populated areas and not the larger communities along the A428 corridor leaving residents of Cambourne which the reason for being built was as a feeder community to Cambridge with a nightmare road journey into the city and no rail alternative, not to mention those from St Neots and elsewhere, who the hell makes these decisions,!! Good luck with your campaign to get slip roads to/from the A428 and M11. Regards, Phil Daley.

  • Hi.
    Would be good to see a 60 mph speed limit on the A14 from before the B1047 up to meeting the M11.
    1. busy queuing interchanges
    2. reduced road noise in an increasingly populated area
    3. better, more measured flow

    Impington ?