The 18.5km (11.5 miles) line, running between Pelaw and South Hylton, was launched on 31 March 2002 and has seen about 17.5 million passenger journeys.

It passes through some of Sunderland's key redevelopment areas and also provides a link to Newcastle Airport.

A �6.9m revamp of Sunderland station is planned for the autumn.

Joe Lawson, vice chairman of the Tyne and Wear Passenger Transport Authority (TWPTA), said: "Metro has changed the face of transport in Sunderland and increased the number of people travelling by rail in the city."

Network-wide revamp

He added: "It also brings shoppers into the city centre and visitors to attractions like the Empire, Winter Gardens and National Glass Centre.

"It's a fantastic asset to have as we seek to bring new jobs and homes to the riverside."

Passenger boardings on the Metro in Sunderland are up from 3,197,658 in 2002/3 to 3,580,057 in 2006/7, according to Nexus.

The government is currently considering proposals for a �600m revamp of the Tyne and Wear Metro, submitted by the TWPTA and Nexus in January.