For centuries, there was only one bridge across the Grand Canal, perhaps the world’s most magical stretch of water. The third and last one went up 73 years ago. Those facts alone would have been enough to draw a crowd as the center span of a new bridge, a sleek red steel spine nearly 190 feet long, was carefully fitted into place on Saturday.

But this crucial moment in the construction of the new bridge drew a vocal little pack of Venetians for other reasons: It cost a lot. It was delayed. It will be hard for people in wheelchairs to cross. And perhaps most of all, the bridge is defiantly, if elegantly, modern — a departure, love or hate it, that has Venice asking if this is how it wants to define itself.