Near as I can locate it, here's what the area looks like today. The bridge was replaced with a tunnel under the harbour entrance.

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A surprising number of these structures were constructed in many countries. Refer to Flying Bridges by Cyril J. Wood for a thorough history including those still in use.

Transporter bridges.

They were an interesting solution to a specific logistics problem (how to get across a river close to water level without major detours through long ramps and without hampering water traffic). Although I wonder how they compared commercially to the ferries they replaced. And how they compared to other solutions like drawbridges. They do look expensive, after all.

Taking issue with the remark about the Americans destroying the bridge. At least some sources indicate the Germans destroyed the bridge 8/22/44 along with demolishing much of the port, as the Free French fought their way into the city. One tower remained standing until September 1945, when it was brought down.

Wikipedia indicates it was blown up by the Germans.

"On the 22nd of August 1944, the German military blew up the bridge to block the port during the liberation of Marseille, but only the north tower fell into the water. The rest collapsed on the first of September, 1945, following the firing of 400 kg of explosives."

Wonderful picture of the "Pont transbordeur de Marseille." Built in 1905 to allow people to cross 'Le Vieux Port'.
Contrary to what I wrote above, the bridge was closed and condamned for destruction at the end of 1943 for requisition its steel. It was finally blasted by German on August 22, 1944 to block the port.