WILMINGTON — Delaware Gov. John Carney pitched three northern Delaware locations, including a former Claymont steel plant where a train station will be developed, as spots for Amazon’s second North American headquarters.

The sites, according to Delaware leaders, meet the major requirements of Amazon’s request for proposals.

Amazon said it wants a site within 30 miles of a population center of at least 1 million people, with proximity to an international airport with daily flights to Seattle, San Francisco, New York City and Washington, D.C., and easy access to mass transit, and major highways. Amazon also sought initial space of 500,000 square feet, with possible total space up to 8 million square feet, which Delaware’s site options would accommodate.

“Delaware checks all of these boxes,” said Cerron Cade, director of the Delaware Division of Small Business, Development and Tourism.

Amazon’s has said it will bring $5 billion of investment and 50,000 jobs over the next 15 years with its second headquarters.

Amazon, which is incorporated in Delaware in 1996 and now has fulfillment centers in New Castle and Middletown, has said it will make a selection for its second headquarters next year. Its existing headquarters is in Seattle.

Gov. Carney noted the emphasis on the Wilmington area was necessary because of the requirement for proximity to the urban population. Philadelphia is the only city within that reach of Delaware.

“First State Crossing” — which includes 425 acres at the former Evraz Steel Mill — is 20 miles from City Hall in Philadelphia, and 13 miles from the Philadelphia airport. It is a third of a mile off Interstate 95.

The location is the site of the proposed Claymont train station.

The second location Gov. Carney mentioned is a combination of properties, totaling 82 acres, on South Market Street along the Christina River in Wilmington. I-95 is a quarter mile away from the location and the Wilmington train station is a third of a mile away. It is 27 miles from Philadelphia’s center city.

A third location proposed is 1800 Concord Pike, Fairfax, which has 500,000 square feet of existing office space available. It currently is home to AstraZeneca and a large JP Morgan Chase facility. It is a mile off I-95 and 26 miles from Philadelphia.

The Concord Pike location would be a place where Amazon could get started. The first two would be places where the full headquarters could be located.

“Delaware is extremely well-positioned to be the home of Amazon’s second North American headquarters, and we believe that Delaware has submitted an aggressive, competitive proposal worthy of Amazon’s consideration,” said Gov. Carney. “Delaware has great communities to live and raise a family, low taxes, responsive leadership, and a central location that has long been a great place for businesses to grow and create good-paying jobs. We look forward to talking more to Amazon about their options in Delaware.”

Gov. Carney said the Amazon proposal has been much different than the usual quiet manner of wooing companies.

Some of the Amazon proposal is confidential, he said.

“This has been much different from the beginning,” said Gov. Carney. “Amazon was very straightforward in coming out and inviting proposals from every state and every region, and they got them.”

In addition to the strength of the sites, Delaware’s application focused on the state’s low tax burden, central location, comparatively affordable cost of living, highly trained and educated workforce, transportation flexibility, connectivity speed, and significant cultural and recreational opportunities.

Delaware’s response also included a package of incentives, according to the governor’s office. The state said companies considering expanding in Delaware have access to a number of programs designed to encourage growth, including the New Economy Jobs Tax Credit, Business Facility Tax Credit and grants or loans through the Delaware Strategic Fund.

In addition to the pitch to Amazon, Gov. Carney debuted a new video called “Options in Delaware” to promote the state, not only to Amazon but to all prospects.

“The whole idea of our proposal is that Amazon has options in our state,” said Gov. Carney.

He said that is the same message the state’s Prosperity Partnership will pitch.

Gov. Carney said the Amazon proposal offered a chance to weigh the state’s strengths and weaknesses.

“The process of crafting the Amazon proposal has actually been quite uplifting,” said Wilmington Mayor Mike Purzycki Thursday. “It has given us the opportunity to collectively reflect on what’s been accomplished over the years to make our city, county and state wonderful places to live, work, enjoy life and raise our families.”