The delayed work to refurbish one of the tubes for the Elbe Tunnel in Hamburg has now commenced. Work to refurbish the other tube is set to commence shortly. This upgrade is required to improve the tunnel link, which carries a very heavy volume of traffic passing along the A1 Autobahn. This stretch of highway is amongst the busiest in Europe and carries a high percentage of truck traffic. The delay was due to construction activity being carried out on the A1 Hamburg Südost and the Süderelbbrücke bridge.