Sur le Pont d'Avignon

And if tunes about Scottish bridges are any use:

The Dean Bridge of Edinburgh
The Dean Bridge Reel
The New Bridge of Edinburgh
The North Bridge of Edinburgh
The South Bridge of Edinburgh
Dalkeith Maiden Bridge
Lugton Brig
Teviot Brig
Craigellachie Bridge
The Forth Bridge
Crossing the New Forth Bridge

And a bit south of the border, tunes for bridges in Newcastle:

The High Level Hornpipe
The New High Level