For decades low-rise commercial development marched across the rolling hills and winding highways of Gwinnett County like a conquering army greedy for territory.

It sprouted in strip centers and box stores and sometimes in gigantic malls that lured shoppers in their cars from across north Georgia and beyond.

But thanks in part to new zoning regulations, a vision of walkable urban living is gaining a foothold in Atlanta’s largest suburban county.

By using zoning rules to encourage urban development in a few places, Gwinnett officials hope to create jobs, diversify the county tax base and encourage redevelopment in areas that have seen better times. They also hope to entice developers to build amenities like trails and open spaces that encourage people to leave their cars behind.

“We don’t want just development,” said County Commission Chairman Charlotte Nash. “We want good development that’s going to be viewed favorably by the community.”

Gwinnett County isn’t likely to transform into Midtown Atlanta. Most of its 896,000 residents live in unincorporated neighborhoods, and Nash said she supports urban-style zoning only in “the right place.”

Developers are responding to that call. Near the Mall of Georgia, a developer plans to build a densely-packed mix of shops, offices and apartments, along with a 21-story hotel that would be the tallest building in Gwinnett County.

County officials also are devising a new zoning district near Gwinnett Place Mall that would encourage a dense mix of development and buildings up to 25 stories. Similar developments are possible near Jimmy Carter Boulevard at I-85 and at the intersection of U.S. 29 and Ga. 316 near Dacula.

Some residents aren’t sold on the idea. Among other things they worry that big developments with hundreds of apartments will make crowded roads and highways even worse. In Facebook posts responding to an Atlanta Journal-Constitution request for comments, some objected to the proposed 16-acre Mall of Georgia development on Woodward Crossing Boulevard. The immediate is area is largely commercial, though there are two apartment complexes nearby.

“Why does Gwinnett need to develop around the Mall of Georgia area, which is already overcrowded?” said Marla Lenzo Kral of Buford.

The developer, Ivy Creek Partners, plans to build 217,170 square feet of retail space, including a grocery store and a family entertainment center. It also plans 91,200 square feet of offices, 352 apartments and 40 condominiums. The 21-story hotel would surpass the county’s current tallest building, the 17-story Sonesta Gwinnett Place Atlanta hotel on Pleasant Hill Road near Duluth.

The developer also is considering an alternative plan that would feature less office and retail space and more apartments. Attorney Shane Lanham told planning commissioners earlier this month that the developer is still analyzing market conditions as it determines the details.

The planning commission unanimously approved the development, and the Board of Commissioners plans to hold a public hearing on Sept. 27 before making a decision. Nash stressed she has not made up her mind and declined to comment on the development.

To move forward, the developer has requested Regional Mixed Use District (MU-R) zoning. Created by the county in 2014, the zoning allows high-density development and buildings up to 25 stories if projects include pedestrian-friendly amenities like green spaces and trails.

Two other sites already have MU-R zoning. One is the OFS fiber optic plant property off Jimmy Carter Boulevard at I-85, where a developer wants to build a movie studio complex and commercial district. The other is Sugarloaf Crossing at the intersection of U.S. 29 and Ga. 316 near Dacula, where a developer plans to build a mix of mid-rise office buildings and apartments over shops and restaurants.

The county is taking a similar approach near Gwinnett Place Mall, where it is creating the Venture Drive overlay zoning district. Like MU-R zoning, the district would allow dense development and buildings up to 25 stories in exchange for various amenities. The county hopes to finalize the details of the district by the end of the year.

But in a county that has transformed from rural enclave to bustling suburb in a just few decades, some residents say they’ve had enough.

“Every single bit of land does not have to be developed,” Beverly Allen Buckner of Lawrenceville wrote on Facebook. She’s lived in the county for 51 years.

“Gwinnett used to be great,” she said. “The people who live here do not want these. Us long term residents just want to have some of the peace back they we enjoyed living here.”