Long-awaited expanded train service on Amtrak between St. Paul's Union Depot and downtown Chicago is slated to begin May 21.

It's the first time in 45 years there will be twice-daily service from the Twin Cities to the Windy City. The newly christened Borealis service will feature midday daily departures from St. Paul arriving at Chicago's Union station about 7.5 hours later. Trains will leave Chicago's Union Station midmorning en route to St. Paul.

The Borealis will follow the same route as the long-distance Empire Builder, which connects Chicago with Seattle or Portland, Ore., through St. Paul.

Stops in Minnesota include Red Wing and Winona, as well as service to the Wisconsin Dells, Milwaukee and Milwaukee Mitchell International Airport.

The Borealis' coach fares begin at $41 one way between St. Paul and Chicago, slightly cheaper than airfares currently listed on Google Flights. Business class on the Borealis is $98 one way. Discounts are available for children ages 2 to 12, who can travel for half off, with restrictions, students, seniors, veterans, military personnel and their families, and groups.

"A second daily passenger rail service connecting St. Paul to Chicago via Milwaukee is a welcome addition to our transportation system, providing more choices and travel flexibility for passengers," said Nancy Daubenberger, commissioner of the Minnesota Department of Transportation (MnDOT), in a news release.

The Borealis service will reach maximum speeds of 79 mph, and Amtrak expects about 232,000 people will use the service in its first year.

Eastbound Empire Builder trips are often delayed largely because Amtrak trains operate on freight railroad tracks. While passenger rail trains are supposed to have priority, that doesn't always happen. In 2023, Empire Builder trains arrived on time about half of the time, according to Amtrak. With eastbound train service originating in St. Paul, rail advocates say it's less likely there will be serious delays heading to Chicago.

The upgrade cost at least $53 million, with costs shared between Minnesota, Wisconsin, Illinois, Amtrak and the federal government. Some of the money was used to upgrade freight track between St. Paul and Chicago. The Winona station's tracks, grade crossings, and signals were improved, as well. What it will cost to operate the line was not available Wednesday.

Rail advocates have pushed for at least a decade to enhance train service between the Twin Cities and Chicago, but the effort at times has been slowed by opposition coming from Republican lawmakers in Wisconsin and Minnesota.

"This makes a real difference for college students, families with kids, and elderly people who really need a transportation option rather than driving and flying," said Brian Nelson, president of the rail advocacy group All Aboard Minnesota.

The train works "for people who want room, comfort and luggage allowment, plus the ability to work, read a book and just relax and ride along the beautiful Mississippi River," he said.

More expansion of passenger rail may be in store in Minnesota. The proposed Northern Lights Express service between the Twin Cities and Duluth is being studied. And last year, the legislature directed MnDOT to study transit needs, including rail, along the Twin Cities-Saint Cloud-Fargo/Moorhead corridor. The study is due next February.