A Modena-Ferrara cycle route is published by various sources. As far as I know, the route as a whole is not officially recognized, although it traverses at least three official cycle paths.
On Aug. 9, 2012, I rode the length of the route and made detailed field notes. My subsequent updates to the relevant OSM data will link to this diary entry.
The Modena-Ferrara cycle route is composed from three distinct asphalt-surfaced rail-trail cycle paths, with the gaps between them connected by low-traffic rural roads. Of the 90 km. route, only two 700 m. segments are unpaved; those are well-graded, drained, compacted fine gravel. The entire route is usable by any bicycle with reasonably robust tires (ca. 28 mm min. width or, with extra care on the short unpaved portions, perhaps as narrow as 25 mm).
Temporary Detours: S. Felice and Finale
Due to severe damage inflicted by the earthquakes of May-June 2012, routing through the central historic districts of S. Felice sul Panaro and Finale Emilia is interrupted. Street blockages are temporary and change as restoration progresses, so I have not mapped alternative routes. Riders through these town centers will need to adjust their routing ad-hoc until the damaged structures are stabilized or removed and the streets reopened.
No other portions of the route are interrupted due to earthquake damage, although rail-trail width is reduced at some sites by barricades around adjacent unstable structures.