Free Wi-Fi has been rolled out to tube stations across south London.
The service, which was originally unveiled for the Olympics, has been extended along the Northern Line from Clapham North station to Balham station.
This will also include Clapham Common and Clapham South.
Wi-Fi is already available at District Line stations Wimbledon Park and Southfields.
A further 28 stations will be connected early next year, bringing the total to 120.
Access will be free for all until the end of January 2013, when those not with Virgin Media, Vodafone or EE will have to pay £2 per day, £5 per week or £15 per month for full internet access.
Virgin estimates that three quarters of Londoners will be able to use the service for free. More than 800,000 people have already subscribed to the service.
To access the internet, passengers need to just connect to the Wi-Fi network, then open and refresh a browser window, which will open Virgin Media’s portal screen.
This portal will provide free transport info and London news to everyone.
Registered customers can then access the full internet by entering their email address.