How would you score it? Where is the start/finish of the bridge? The onramp or the expansion crack or the toll booth... I'm sure there must be a formal definition of such things, for world records or taxation turf.

Wikipedia says,
Note: There is no standard way to measure the total length of a bridge. Some bridges are measured from the beginning of the entrance ramp to the end of the exit ramp. Some are measured from shoreline to shoreline. Yet others are the length of the total construction involved in building the bridge. Since there is no standard, no ranking of a bridge should be assumed because of its position in the list. Additionally, numbers are merely estimates and measures in U.S. customary units (feet) may be imprecise due to conversion rounding.



https://en.wikipedia.org/wiki/List_o...s_in_the_world

The new Bay Bridge from Oakland to SF has a bike path but it's not finished yet. The website says they need to finish demolishing the old west span before finishing it. Google Maps cycling directions from Oakland to SF uses the ferry. I'm thinking it will be about five miles but it's sort of cheating, since it's two bridges with an island in the middle.

BICYCLE AND PEDESTRIAN PATH | Bay Bridge Info