The Split Rock is an interesting area of the I and M Canal in LaSalle County. During the construction process at this site, the canal workers blasted a passage through a ridge of limestone. The interurban electric line the Chicago, Ottawa, and Peoria constructed a bridge across this passage.
The bridge was a lost Pratt through truss bridge. It is no longer present. The photos above are obtained from the internet.
On one side of the passage, the Chicago, and Rock Island constructed a tunnel through the rock ridge.