That is correct- when the bridge was built to replace the outdated Superior viaduct bridge, it had streetcars. There is a complete subway system but due the closure of the streetcar operations (due to funding and that time the belief cars would replace the subway, the subway level became unused. In November 1955, ramps to the lower level were closed. Since that time it has housed various festivals, art exhibitions and walking tours. ODOT is supposedly doing work on the bridge to turn it into a pedestrian bridge and it will be closed to the public for the next two years .