Google just announced that Google Fiber will be coming to Atlanta, Charlotte, Nashville, and Raleigh-Durham, with the gigabit Internet service hitting 18 cities across those four metro areas.

That brings the total number of Google Fiber metro areas to seven, including previously announced locations Kansas City; Provo, Utah; and Austin, Texas. Another five are still being considered; Google promised updates on Phoenix, Portland, Salt Lake City, San Antonio, and San Jose later this year.

"Bringing Google Fiber to these cities is a long-term investment. We’ve been working closely with city leaders over the past year on a joint planning process to get their communities ready for Google Fiber—and now the really hard work begins," Google Fiber VP Dennis Kish wrote today. "Our next step is to work with cities to create a detailed map of where we can put our thousands of miles of fiber, using existing infrastructure such as utility poles and underground conduit, and making sure to avoid things like gas and water lines. Then a team of surveyors and engineers will hit the streets to fill in missing details. Once we’re done designing the network (which we expect to wrap up in a few months), we’ll start construction."

The new cities to get Google Fiber are Atlanta, Avondale Estates, Brookhaven, College Park, Decatur, East Point, Hapeville, Sandy Springs, and Smyrna in Georgia; Nashville-Davidson in Tennessee; and Charlotte, Carrboro, Cary, Chapel Hill, Durham, Garner, Morrisville, and Raleigh in North Carolina.

Google didn't provide a specific timeline but said it will have to work with city officials "over the next several months" on the detailed network design before it can begin construction.

Offering symmetrical gigabit Internet for $70 a month or 5Mbps service for free (with a one-time construction fee of $300), Google Fiber provides a welcome alternative to DSL and cable in the few areas where it exists. Google Fiber doesn't have the geographic reach of Verizon's FiOS fiber-to-the-home service, but Verizon is nearing the end of its buildouts. AT&T is also building fiber in some areas, but its CEO threatened to pull the plug on deployments if the federal government regulates Internet service more heavily. Google doesn't seem to be bothered by heavier regulation, even suggesting that new rules could help the company obtain access to utility poles, rights-of-way, and other infrastructure.

An AT&T spokesperson said today that the company's fiber plans are moving along, despite its earlier statements. "We’ve launched U-verse with AT&T GigaPower in five markets including Austin, Dallas-Fort Worth, and several cities in North Carolina," AT&T told Ars. "Beyond that, we’ve announced plans to expand to 12 additional markets including Atlanta; Charlotte and Greensboro, North Carolina; Chicago; Cupertino, California; Houston; Jacksonville, Florida; Miami; Nashville, Tennessee; Overland Park, Kansas; St. Louis; and San Antonio. And, more broadly, we are working with local officials to determine where there are solid investment cases and policies so that we might bring U-verse with AT&T GigaPower to as many as 100 communities nationally."

Google Fiber went live in Kansas City in Kansas and Missouri in November 2012, in Provo, Utah in early 2014, and is now doing its first deployments in Austin, Texas.

Some cities and towns, fed up with private broadband providers, have built their own networks or taken other steps to boost Internet service for residents. Municipal broadband has been held back by laws designed to protect private Internet service providers from competition in 19 states, but Democrats in Congress and the Federal Communications Commission are looking into whether those laws can be overturned.