Plans for America's latest megamall, near Miami, include indoor skiing and ice skating.

The giant complex also would have water ballet fountains, a performing arts center and a submarine ride.

And, of course, millions of square feet of space for stores.

When the Mall of America opened in Bloomington nearly a quarter-century ago, it was unique — bigger and more spectacular than any other shopping destination in the United States. People who had never been to Minnesota booked plane tickets to see it.

These days, over-the-top retail destinations are appearing around the world. In a battle for the attention of shoppers who can get virtually anything they want online, mall developers are creating gigantic complexes that blur the line between retail and entertainment.

The Mall of America's Canadian owner, Triple Five Group, is working on both the Florida project and one in New Jersey — each branded under the grandiose name "American Dream" — that could surpass Minnesota's marquee mall in size. Meanwhile, King of Prussia Mall outside Philadelphia now has 450 stores that span 2.9 million square feet of retail space, nearly as much as the Mall of America.

Several malls in Asia dwarf anything in the United States, and one in Canada is accredited as a zoo.

"We're so fickle these days, and we want to be entertained," said Deb Carlson, retail director at Cushman & Wakefield/NorthMarq and past president of the Minnesota Shopping Center Association. "I think the big malls do a whole lot of that by virtue of being large and having a huge plethora of shops and entertainment."

Last year's $325 million expansion of the Mall of America restored its bragging rights as the nation's biggest mall, a claim that had been in question for some time depending on how you measured. But it is unlikely to end the ongoing pressure malls feel to get bigger and glitzier to give shoppers a reason to keep coming back.

With department stores struggling and online competition growing, it is essential to stand out.

On one side, the big malls compete with tourist destinations that add to or refresh their attractions each year. But they also need to outpace smaller regional malls that are renovating and adding new stores, amid fears that the weakest of them may not survive.

"The malls are at risk," Carlson said. "I think they have been for a while. … There's a fear that some of these malls aren't going to stay open."

The Mall of America already has a huge indoor amusement park and aquarium. But it continues to add features such as the Crayola Experience, new rides such as FlyOver America and new-to-the-market restaurants such as Jimmy Buffett's Margaritaville. It also draws big crowds for the 400-plus events it hosts each year, including many celebrity appearances.

Its latest addition brought it a new front entrance as well as a JW Marriott hotel, an office tower and 165,000 square feet of retail space. That space is still being leased out but already includes eateries such as Shake Shack and highly anticipated shops such as Zara and a flagship Anthropologie, both set to open later this year. Altogether, the mall now has 5.6 million square feet of building space, 3.2 million of it for retail.

"People are always looking for that opportunity to check out the largest, the biggest, the newest," said Jill Renslow, the Mall of America's senior vice president of marketing and business development. "We continue to develop because we want to keep this property fresh. … That's what is key to our success so that it doesn't become stale."

And it's not done. With a new luxury wing in the planning and more land to expand, the Mall of America is already working on what comes next.

Staying on top

As regional malls face an uphill battle, they're also upping their game. Some of their answers to survival might come from the megamall playbooks.

Many of those malls have the same stores and are not too far from another, said Carlson. So they are having to find new ways to differentiate themselves to stay relevant. The most obvious way to do that is to lure unique tenants.

Ridgedale Center last year got the only Nordstrom department store in the Twin Cities market outside the Mall of America. Rosedale Center is adding the market's second Von Maur, and the Galleria in Edina continues to draw new-to-the-market stores such as Sundance and Tory Burch.

At the same time, there's been a shift among the national brands. Many mall stalwarts such as the Gap and Aeropostale are on the decline. Macy's, a major anchor at many shopping centers, is trying to reinvent itself and is closing 100 stores across the country early next year. The future of Sears, another big anchor store, is uncertain.

To better compete, shopping malls both big and small have been in a big redevelopment boom in recent years, adding more entertainment, said Stephanie Cegielski, a spokeswoman for the International Council of Shopping Centers.

"We're seeing all types of different things from restaurants and movie theaters to climbing walls and fitness centers," she said. "The Mall of America is the extreme example of that. … Not all malls are going to do it at that scale, but they're definitely trying to diversify their tenants to draw a bigger audience."

Thinking big

The Mall of America's owners continue to think big.

The sprawling American Dream Meadowlands under construction in New Jersey, just outside New York City, has been in the works for more than a decade and has dealt with a series of setbacks and delays. It is now slated to open by mid-2018. When it opens, it will be anchored by Saks Fifth Avenue and Lord & Taylor and will feature a bigger Nickelodeon Universe than the Mall of America. But with 3 million square feet of retail space, it appears it will be, initially at least, a bit smaller than the Mall of America.

The American Dream Miami is being billed as being bigger than the Mall of America. The project, still in development, calls for more than 6.2 million square feet in total retail and entertainment space.

Dave Brennan, a retailing professor at the University of St. Thomas, doesn't think the Mall of America has too much to worry about from megamalls in other regions of the country. When the Bloomington mall first opened, it was such an oddity that it initially drew tourists from around the world. Now it's more of a secondary reason for people to come to the Twin Cities, he said.

"It depends increasingly on the local and regional customers for the lion's share of its customers," he said. "Customers coming from beyond 150 miles are much less important today than they were in the 1990s."

Still, Mall of America executives think it retains its global appeal. After all, as they often like to note, with more than 40 million annual visitors, surpassing even Disney World, it's one of the top U.S. attractions.

Up next is an addition in the planning stages called "The Collections at MOA," a luxury retail wing conceived to be a big tourist draw.

The initial plan calls for a $500 million project that would add 1 million square feet for high-end boutiques, a luxury hotel and more office space. The timeline is still up in the air as the mall works with upscale brands to nail down leases and to design the new space with them.

"It's going to be an amazing experience for this marketplace to bring the convenience of those luxury brands here rather than having to go to Chicago or Miami or New York or Las Vegas," Renslow said. "We'll also be able to attract those visitors from across the nation to come here."

Beyond that, the mall is in discussions about developing nearby land.

"We have potential to double in size yet," she said.

Kavita Kumar • 612-673-4113