Wacker Drive is a major multilevel street in Chicago, Illinois, running along the south side of the main branch and the east side of the south branch of the Chicago River in the Loop. The vast majority of the street is double-decked; the upper level intended for local traffic, and the lower level for through-traffic and trucks serving buildings on the road (and originally a dock). It is sometimes cited as a precursor to the modern freeway, though when it was built the idea was that pleasure vehicles would use the upper level. It is the only street in the city that is prefixed with all four cardinal directions, albeit on different parts of its route. The drive is named for early 20th century Chicago businessman and city planner Charles H. Wacker. The upper level is normally known as Upper Wacker Drive and the lower level is Lower Wacker Drive. A short part has a third level, sometimes called Lower Lower Wacker Drive or Sub Lower Wacker Drive. History In 1909, architects Daniel Burnham and Edward H. Bennett drew up a plan for the Commercial Club of Chicago to unify the city's urban design and increase its physical beautification. The improvement of traffic flow in Chicago was a major part of the plan. Among its many recommendations was a double-decked roadway along the river, intended to relieve the congestion at River Street and Rush Street, where 50% of the city's north–south traffic crossed the Chicago River. Charles H. Wacker, chairman of the Chicago Plan Commission, pushed the idea. The original double-decker road, replacing South Water and River Streets, was completed in 1926 at a cost of $8 million and named after Charles Wacker. The 1926 section stretched from Lake Street to Michigan Avenue, the latter of which was also rebuilt into a two-level road. An extension south to Congress Parkway and Harrison Street was built between 1948 and 1954, replacing Market Street (after the Market Street stub of the Lake Street Elevated was removed). Extensions east were built in 1963 and 1975, with the latter taking it to Lake Shore Drive, and a new lower level starting at Stetson Avenue. At the time, Lake Shore Drive had an S-curve at the river, running where Wacker now goes between Field Boulevard and current Lake Shore Drive. This S-curve was on a viaduct over the Illinois Central Railroad's rail yard, and was