The City Council on Thursday unanimously approved a plan to blanket the city's 135 square miles with a high-speed wireless Internet connection, a measure the mayor is expected to sign soon.

If the system is fully deployed by the third quarter of 2007 as planned, Philadelphia would be the first large city to have its own wireless Internet network. EarthLink Inc. will build, operate and maintain the network under a 10-year contract.

"Philadelphia is a city of many firsts and this is a first as well," Councilwoman Blondell Reynolds Brown said after the vote that sent the measure to Mayor John Street. "It's the first time a large municipality is saying we'll take an aggressive role in ensuring that the digital divide is bridged."

EarthLink will start building the network in June over a 15-square-mile test area that would cover parts of North and South Philadelphia. The test should take three to four months, said Clifton Roscoe, director of major projects for EarthLink.

Councilman Brian O'Neill said EarthLink has the choice to get out of the deal if the company doesn't like the results of the trial. But he added that he believes EarthLink will succeed.

The Internet service provider's first target would be the city's quarter-million dial-up customers plus existing broadband subscribers who want to pay lower prices, O'Neill said.

Community-based organizations will reach out to low-income households to get them interested.

Atlanta-based EarthLink will invest $22 million over a decade to provide Wi-Fi in the city. Prices are expected to be about $20 a month, or $9.95 for low-income households. EarthLink has agreed to lease capacity to rival Internet service providers.

About 300 communities across the country are developing or have deployed Wi-Fi plans. Chicago and San Francisco also are planning big public Wi-Fi projects.

O'Neill said having citywide Wi-Fi will attract business and leisure travelers to Philadelphia.

"This puts us at the top of the list," he said.