Urban journal explores sub-Loop tunnels

Urban journal explores sub-Loop tunnels

Iker Gil is editor-in-chief of MAS Context, which “addresses issues that affect the urban context.” In the Spring 2011 issue, transportation expert Bruce G. Moffat explains why and how the tunnels – accommodating a subterranean freight railway – were constructed 40 feet below almost every street in downtown Chicago. There are nearly 40 miles of tunnels down there, originally intended to divert freight from congested streets above. They were largely forgotten for many years until 1992, when a tunnel below the Chicago River collapsed, causing an estimated $1 billion in damages.

Spring 2011 issue of MAS Context

(Above) Detail of a 1925 map of Chicago Tunnel Company and Chicago Tunnel Terminal Company. At the very center of this image is the block on which Marina City was built 35 years later. The tunnels, represented by black lines, appear to go around and through the 300 block of North State Street, which runs left to right. (Image from Bruce Moffat Collection. Click to view larger version.)

At the time, the block was owned by Chicago & Northwestern Railroad, which was formed by a merger of several rail lines including Galena & Chicago Union Railroad. Handwritten letters on the map appear to spell “C&N WAY,” “GAL DIV,” and “GAL IN.”