Ambitious plans are being considered that would see the Metro system extended into communities, towns and business parks.
The North East Combined Authority has agreed a strategy for investment in Metro and local rail.
The Metro and Local Rail Strategy identifies a network of disused or under-used rail routes that could be used to put towns and communities on the railway map.
The Strategy, approved by the Leadership Board, also sets out the case for more than £1bn of new investment in the existing Metro system over the next 20 years.
Coun Nick Forbes, lead member for Transport on the North East Combined Authority, said: “We have approved an ambitious strategy for expansion of local rail across our region, tied in with continued investment, development and expansion of the iconic and world-famous Metro system.
“We are building a business case for major investment in Metro and local rail to improve journeys for passengers and provide cleaner, greener and attractive travel choices.
“Local rail brings huge economic and social benefits to the communities it reaches today but we need to extend those benefits into new areas.”
Plans could see the system extended to Ashington, Peterlee, Washington, Cobalt Business Park, Team Valley and the Metrocentre.
As well as extending the service, the strategy also looks at replacing the Metro fleet and facilities.
Nexus, which owns and manages Metro, has begun talks with the Government about funding routes and will submit a detailed business case before the end of this year.
Tobyn Hughes, managing director for transport at the Combined Authority, said: “We believe some existing and disused local rail corridors can be combined with Metro to create a single network at a lower cost than new-build railways.
“By fusing local rail and Metro together we can create something new and better than the sum of those two parts.
“There are also areas where the existing Metro system can be upgraded, and the system is badly in need of a new fleet. This opens the possibility of a new Metro fleet working seamlessly alongside regional trains depending on the route and stations being served.
“Nexus, which owns and manages Metro, will have invested £350m by 2021 renewing track and other vital infrastructure – it needs to continue that investment over the next two decades but we must also now focus on the trains as well.”