Amazon announced Thursday it plans to build a second headquarters that would cost as much as $5 billion and house up to 50,000 employees. But the question is, where will it set up shop?

The Seattle-based online retailer's new location, called "HQ2," must be in a North American metropolitan area with more than 1 million people, and a "stable and business-friendly environment," according to a statement from the company.

"We expect HQ2 to be a full equal to our Seattle headquarters," Amazon founder and CEO Jeff Bezos said in the statement. "Amazon HQ2 will bring billions of dollars in up-front and ongoing investments, and tens of thousands of high-paying jobs."

A few dozen metropolitan areas in the U.S., Canada, and Mexico would fit the population requirement. Amazon also is prioritizing locations that are within 45 minutes of an international airport and near a strong university system, The Wall Street Journal reports.

The company called for proposals for the new site, which could create fierce competition among cities eager to bring in new jobs and spur development of their business communities. Bids are due by Oct. 19, and Amazon says it will choose one sometime next year.