MINNEAPOLIS — Minnesota is hoping to host the first World’s Fair on U.S. soil in nearly 40 years, but it will have to overcome bids by Poland’s third-largest city, Lodz, and the Argentine capital of Buenos Aires when a winner is selected in the coming days.

The events that introduced the world to the Eiffel Tower, Space Needle and Ferris Wheel have lost some of their cultural relevance in an age of globalization and cheap air travel. But World’s Fairs – now referred to as World Expos for the largest events held every five years and as specialized expos for smaller ones in other years – still draw millions of visitors and allow hosts to show off.

The Bureau of International Expositions will choose the site of the 2022 or 2023 specialized expo Wednesday in Paris. Minnesota’s theme is health and wellness, Lodz’s is the reinvention of cities and Buenos Aires’ highlights creative industries in the digital era.

Here’s a closer look:

WHAT ARE EXPOS?

According to the BIE, expos are global events aimed at “educating the public, sharing innovations, promoting progress and fostering cooperation.” They’re meant to bring the world together to find solutions to some fundamental challenge of humanity. Visitors tour pavilions where participating countries and organizations showcase their contributions on the theme, while experts and diplomats attend conferences on the sidelines.

Six-month-long world expos are held every five years, while smaller, three-month “specialized expos” on specific themes, which are what the BIE is currently considering, fall in between. World leaders often visit.

“Expos remind us that there is much more that binds us together than separates us,” Jim Core, director of the International Expositions Unit at the State Department, said by phone from Paris on Friday.

Many Americans have lost sight of how big these events are because the U.S. hasn’t hosted one since New Orleans in 1984, but the Milan World Expo in 2015 drew around 20 million visitors, according to the BIE. This summer’s specialized expo on Future Energy in Astana, Kazakhstan, drew 4 million people, and the 2020 Dubai World Expo is expected to draw about 25 million, the BIE says.

HEALTHY MINNESOTA

Minnesota has proposed a specialized expo for 2023 on the theme “Healthy People, Healthy Planet.” It would trade on the state’s reputation as a center of innovation and excellence in health and wellness, the leader of the bid committee, former Minnesota Secretary of State Mark Ritchie, said from Paris. Minnesota is home to world-class health care institutions including the Mayo Clinic, medical device makers such as Medtronic, and insurers such as UnitedHealth.

The site would be near the Mall of America, one of the country’s biggest shopping centers, which is located in the Minneapolis suburb of Bloomington. The committee projects that it will draw around 12 million visitors, including nearly 220,000 international visitors, with a total impact on the local economy of $1.5 billion.

The State Department is vigorously lobbying on Minnesota’s behalf, a bigger diplomatic effort than Poland’s or Argentina’s, Ritchie said. It has hosted events in Washington, Paris and other cities, while its embassies and consulates around the world are promoting the bid. It also brought foreign ambassadors to Minnesota. Deputy Secretary of State John Sullivan will be in Paris to cast the U.S. vote.

The U.S. left the Bureau of International Expositions in 2001 as congressional interest waned following the end of the Cold War, said Matthew Asada, the State Department’s expo program officer. But President Trump signed a bill in May, the “U.S. Wants to Compete for a World Expo Act,” to rejoin and put the U.S. back in the game.

REVITALIZED POLAND

The bid theme of the central Polish city of Lodz for 2022 is “City Re: Invented” and focuses on the revitalization of post-industrial cities. The city’s expo website says the event would kick-start a second wave of modernization and share Poland’s expertise in “urban regeneration” with the rest of the world.

Lodz is Poland’s third-largest city, an hour away from the capital Warsaw. The city expects about 8 million visitors.

CREATIVE ARGENTINA

Buenos Aires has offered a 2023 expo on “Creative Industries in Digital Convergence.” If approved, it would be the first expo in Latin America under the auspices of the BIE, which began operations in 1931. Several were held in Latin America before then, though.

“It will be a celebration of human creativity, in which no one should be left out,” Argentine government minister Gabriela Ricardes said in a presentation to the Organization of American States. Buenos Aires expects over 6 million visitors.