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Transport strategy

Inner orbital area study

The inner orbital area encompasses the strategic cross-regional routes around the southern outskirts of London.

It includes the M25 London Orbital motorway, which is the busiest and most congested highway corridor in the South East area. It also includes the roads that serve Heathrow Airport, the Medway Ports, and Thamesport.

There are marked variations in wealth and prosperity between the Inner Orbital corridors. Those that pass through north Surrey and Berkshire are among the most prosperous in the South East, whereas those in North Kent are among the most deprived. Housing affordability is also hugely variable across this area.

Study completion: December 2021


  • Economic imbalance – the east has higher deprivation but greater housing supply, the west is prosperous but faces supply challenges
  • Orbital rail connectivity/journey times is poor from Reading to Gatwick to Ashford, constraining the development and growth potential of the Gatwick Diamond and other major economic hubs
  • Severe congestion on the M25 Orbital Motorway and limited scope for additional highway capacity on this corridor
  • Sustainable surface access to Heathrow from the South East is limited


  • Rail connectivity enhancements east-west through Gatwick Airport
  • Possible missing links between the M3 and M4 motorway, to help alleviate congestion on the M25 and support local development
  • Opportunities for demand management
  • Potential for Western Rail Access to Heathrow, Southern Rail Access to Heathrow, and mass rapid transit solutions
  • The need (and associated challenges) to integrate with the proposed Lower Thames Crossing to support strategic connectivity