MINNEAPOLIS - Crews have layed thousands of weldsgetting the new Central Corridor LRT line ready for business.

But onWednesday, one particular weldmarked a significant milestone, one that mass transit riders across theTwin Cities are celebrating.

Crews joined the Central Corridor light rail track to existing Hiawatha light rail track when they welded the two lines together between the Metrodome and Cedar Riverside LRT stations.

"This connection will create a 63-mile passenger rail network for the Twin Cities, 11 miles for Central, 12 miles for Hiawatha and 40 miles for Northstar," said Mark Fuhrmann, the local program director for New Starts rail projects, which includes Central and Southwest."The network will increase to 78 miles when the 15-mile Southwest LRT line begins service in 2018, four years after Central Corridor."

Central Corridor LRT trains from St. Paul will operate for a mile in downtown Minneapolis from a point near the Metrodome, serving five stations over existing Hiawatha tracks to Target Field Station.

Passengers will be able to board at Union Depot in downtown St. Paul and travel to the University of Minnesota and downtown Minneapolis or transfer at Metrodome Station to the Hiawatha line to reach the Mall of America or the Minneapolis-St. Paul International Airport.

"This weld is our own version of the golden spike for the transcontinental railroad as it connects the Twin Cities of St. Paul and Minneapolis," Fuhrmann said. "By connecting Central Corridor Green Line with the Hiawatha Blue Line, we will expand environmentally friendly, affordable transit options for residents of St. Paul, Minneapolis and the region."

Once Southwest is built, riders from Eden Prairie will be able to ride the future 26-mile Green Line through downtown Minneapolis to the University of Minnesota, state Capitol area and downtown St. Paul without changing trains. They also will be able to transfer to the Hiawatha or Northstar lines at the Interchange being built at Target Field Station.