Metro plans to introduce its first free transfer between rail stations on Friday, allowing riders to connect between the Farragut West and Farragut North stations without paying a second fare.

Dubbed Farragut Crossing, the "virtual tunnel" between the two stations will open at noon, with local officials on hand to kick it off.

Riders shouldn't expect to see any actual bridges or tunnels between the two stations. Instead, they will have to leave the stations and walk about a block outdoors. They won't be charged for re-entry into the system.

Riders will have 30 minutes to meander between the stations, Metro spokesman Dan Stessel said. Consider it the food truck transfer, giving riders enough time to get a snack at one of the many food trucks that stop at Farragut Square. The local business improvement district had asked for a long-enough transfer window for riders to be able to stop at businesses en route to the next station, Stessel said.

The idea for a connection between the two stations has been kicked around for years. But building an actual tunnel would have been costly and difficult in the developed downtown area.

The virtual tunnel cost Metro an estimated $500,000, Stessel said. It entailed months of computer programming and testing to let Metro's SmarTrip cards and faregates recognize the transfer. Metro also asked the District to repair some sidewalks and curbs in the area to smooth the walk between the two stations, District Department of Transportation spokesman John Lisle said.

The idea is to take some of the pressure off Metro Center, the only current transfer point between the Orange/Blue and Red lines. It will allow riders to skip a few stops and give them an alternative if there are problems or crowding at Metro Center.

Metro plans to advertise the change with signs at Metro Center and possibly a pamphlet, Stessel said. But it won't be featured on Metro's map -- or even the new version that is slated to be rolled out next summer.

"It's viewed as a fare policy more than a feature of the map," Stessel said.

If all goes well with the Farragut Crossing, Metro has said it may consider adding a similar transfer between Gallery Place and Metro Center, giving riders more transfer options among all five lines at the two crowded hubs. "We want to see how this one goes before we consider any others," Stessel said.