With just over two weeks to go until the Parkway East closure, Thursday marked a big day for the historic Commercial Street Bridge Project. At 6 a.m., crews closed Commercial Street, which runs under the bridge, to do a test slide of the new bridge. The roadway, as well as nearby Forward Avenue and a portion of Nine Mile Run Trail, will be closed to traffic from 6 a.m. to 4 p.m. "I mean, it sounds simple to just slide it, but it's a very complex system. So this is really just a test of that system.