The E.656, called “Caimano”, was a six-axle mixed-traffic locomotive for the 3 kV DC network. Each locomotive had a two-part body that sat on three two-axle bogies to be able to negotiate tight curves. They had six double motors which could be operated in several series and parallel modes. A total of 461 was produced by several manufacturers between 1975 and 1989. The last 58 had push-pull controls and were also called “Navetta”.

The E.656 was also used for express trains until more modern locomotives took over. Later many were rebuilt for a top speed of only 120 instead of 150 km/h and designated E.655 for freight-only service. The first ones were withdrawn in 2010 and soon the remaining ones could be mostly seen only in freight service, but they still hauled passenger trains on Sicily until 2020. The last E.655 were withdrawn from regular service in 2023.