The South Shore Line operated by the Northern Indiana Commuter Transportation District (NICTD) is nicknamed 'the last Interurban' left in America. The electric MU railroad runs for 90 miles from South Bend, Indiana to Millennium Station in Downtown Chicago. The last 14 miles from Kensington into Millennium station sees trains operate via trackage rights on the former Illinois Central, now Metra Electric. The South Shore Line pays Metra approximately $47 per car handled into Millennium Station, with intermediate travel on South Shore trains between 63rd Street and Downtown Chicago prohibited. Service to Hegewisch (located within the city of Chicago) is owned and subsidized by Metra, including the setting of fares.

Service on the South Shore Line is relatively infrequent and concentrated during peak direction rush hours. As of January 2018, the South Shore Line runs 20 eastbound and 19 westbound trains per weekday from Millennium Station, 5 of which turn-around in Gary, the rest run to Michigan City with 5 daily trains extended to South Bend. There are also two late evening/early morning trips only between South Bend and Carroll Avenue which are basically dead head moves from the Michigan City yard since trains can't be stored at the South Bend Airport for long periods of time.

Weekend service is 9 round-trips to Carroll Avenue, and 5 trips extended to South Bend. Most trains make all stops (with some exceptions during rush hours). Since 2015 on weekdays, the Sunrise and Sunset Express trains run to and from South Bend, stopping at only Dune Park and East Chicago, completing the trip in under two hours, instead of the normal 2 hours and a half hours. There is also an westbound express train on weekends (with no return eastbound counterpart).

The nickname the "last Interurban Railroad in America" dubs from the fact trains still run down the middle of 10th and 11th Streets through Michigan City, with the 11th Street-Michigan City stop seeing passengers boarding and alighting in the middle of the street. In addition trains make a few tiny flag stops at Hudson Lake, Beverly Shores and Clark Road, where passengers are instructed to push a strobe light to altert the engineer to stop for them. Until 1994 there were seven additional flag stops along the line, which were closed to provide faster passenger service.

Finally, the South Shore Trains pass through a time change since South Bend is located in Eastern Time. Railroad operations just keep things simple and use Central Time internally for all time keeping, the public timetable has the time for South Bend in parenthesis.