Greyhound is expanding its presence in St. Paul. Starting Tuesday, the venerable bus company will offer six daily departures and additional weekend service from Union Depot to places such as Chicago, Madison, Milwaukee and Kansas City.

Greyhound also will offer two daily Express schedules, the company's premium direct service between major cities.

"It was a natural move to bring our premium Express service to St. Paul after seeing the high demand through the last year in Minneapolis," said Stephen Hutchings, regional vice president of Greyhound Lines. "This latest expansion will offer our customers another convenient and affordable mode of travel between these popular cities.

Greyhound already offers its Express service from it station in downtown Minneapolis.

The news comes as intercity bus riding is experiencing an upswing. A recent report from DePaul University shows that buses are the fastest growing mode of city-to-city transportation in the United States.

DePaul's 2013 "Motoring Into the Mainstream" review of intercity bus services found bus fares were 52 percent lower than rail fares and 79 percent cheaper than advance-purchased airfares. The report found it was 38 percent less expensive to ride the bus than drive. The study found that the average cost of a one-way trip by bus was $30.53, compared with $64.19 by rail and $145.23 by plane.