New statistics revealed Metra provided nearly 87 million passenger rides last year.
Metra officials said that's up 4.2 percent over ridership in 2007 when 83 million tickets were sold.
They attribute the spike to soaring fuel prices and enhancements to their weekend service.
The busiest route last year was the BNSF Railway, which runs between Chicago's Union Station and Aurora.
17 million trips were taken on that route in 2008.
The largest gains in ridership were seen on routes between Kenosha, Wisconsin and downtown Chicago and Antioch and downtown Chicago.