Updated

Travelers on London's Underground need no longer fear being out of touch.

The subway network began launching WiFi on Thursday, rolling out the service to a handful of stations this week as part of a build-up before the Olympics. The games are set for July 27 to Aug. 12.

By the end of the year, about 120 Tube stations will be connected, including some which are very deep underground.

The service will be free for the summer, but users will have to register. After that, a "service portal" will be made available to Tube passengers that will provide subway updates and some entertainment information. Access to the wider Internet will be made available as part of Virgin Media's broadband and mobile subscriptions — or on a pay as you go basis.

London's transportation authority and Virgin flatly declined to discuss the value of the contract, saying it was commercially confidential.

The announcement did not mention plans to introduce cell phone service to the Tube network.

Will it work? London's WiFi network can be clunky at times above ground, but organizers are confident the system will be able to handle the challenge of providing service miles (kilometers) underground.

The WiFi addition is part of a multibillion-pound (multibillion-dollar) effort to upgrade the capital's aging subway network.