The four major wireless operators came together to bring wireless service to the Tip O’Neill tunnel in Boston.

Today, AT&T, Sprint, T-Mobile and Verizon Wireless flipped the switch providing in-tunnel coverage along Interstate 93, the Interstate 90 Connector and all of the associated tunnel on-ramps and off-ramps. This adds to coverage already provided in the Ted Williams, Sumner, Callahan and Prudential tunnels.

“The expansion of service into the Big Dig tunnels is a welcome addition to existing wireless coverage in Boston,” said Mark Elliott, spokesperson for the wireless carriers, in a statement. “A system of this size and complexity – the provision of wireless service throughout an underground interstate highway with numerous on- and off-ramps – is a significant accomplishment. It is the result of a huge and sustained effort by the MTA and the wireless carriers.”

The state-of-the-art wireless phone system serving the Big Dig consists of sophisticated electronics and antennas. Over the coming weeks, the participating wireless carriers will be optimizing their networks and the new system to ensure reliable wireless phone service in the tunnels.