By 1870, the line had extended across the Mississippi and all the way to Nebraska.
The line eventually came under the ownership of Illinois Central. The IC used this as a mainline, connecting to the bigger mainline to Chicago and to New Orleans, Louisiana.
In 1972, the IC purchased its main competitor, the Gulf, Mobile & Ohio Railroad, forming the Illinois Central Gulf Railroad.
The ICG years were bad. The Iowa Division was dismantled, and this line, along with many others were sold to Subsidiary Chicago, Central & Pacific Railroad in 1985.
The ICG changed the name back to Illinois Central in 1988, and purchased back the Iowa Division in 1996.
By then it was too late. Other railroads had been doing well, and competition became too much for the IC. They sold themselves to the Canadian National Railway in 1998, who would later purchase the Wisconsin Central in western Wisconsin and several other railroads.
The CN continues to operate this line with about 5 trains a day.
06/26/21
Located along the Mississippi River in East Dubuque, this tunnel runs at a sharp angle underneath the bluff above.
Built in 1867 as the railroad began approaching the Mississippi River, this tunnel runs at a 90 degree turn underneath the bluff. From here, the railroad crosses the Chicago, Burlington & Quincy (now BNSF) mainline, and into Iowa.
It is known that rock from the tunnel was used as bridge piers on the Mississippi River bridge.
The west portal of the tunnel remains as a standard rock face portal with a square design. However, the east portal was rebuilt in approximately 1899 with a new stone and concrete arch.
The tunnel was constructed using a boring and blasting method. Currently, it is still operated by Canadian National. Chicago Great Western also once operated through this tunnel.
Throughout the history of this tunnel, it has proven to be a bottleneck for railroad operations. Although not a long tunnel, the harsh curve has proven to be an issue.