FS Class 625

FS Class 625

Company type	Steam locomotive class
Industry	Rail transport
Predecessor	FS Class 600
Founded	1910
Area served	Italy
Products	2-6-0 mogul steam locomotives
Number of employees	188 (initial production)

Overview

The FS Class 625 (Italian: Gruppo 625) represents a series of 2-6-0 mogul steam locomotives operated by the Ferrovie dello Stato (FS), Italy's national railway company. These locomotives are affectionately referred to as Signorine—meaning 'young ladies' in Italian—a nickname also shared with the related Class 640 engines, highlighting their elegant and refined appearance compared to other locomotive classes.

Design and Production

The Class 625 was developed as a superheated, simple-expansion evolution of the earlier mixed-traffic Class 600 model. Inspired by the successful implementation of superheating and simple expansion in the Class 640—which itself was an upgraded variant of the older Class 630—the design modifications were applied to this class. Initially, 108 units were manufactured by various Italian firms between 1910 and 1914. Production resumed post-World War I, with an additional 80 locomotives built from 1922 to 1923, including the last 25 produced by Berliner Maschinenbau. The interruption in manufacturing corresponded with the wartime period.

Conversions: Class 625 3xx

Beginning in 1929, the original fleet of 188 Class 625 locomotives was expanded through the rebuilding of older FS Class 600 engines. These earlier models, constructed between 1904 and 1910 by manufacturers such as Gio. Ansaldo & C., Costruzioni Meccaniche di Saronno, and Henschel & Son, were compound and non-superheated, distinguishing them from the standard Class 625s. Between 1929 and 1933, a total of 153 Class 600 units underwent conversion to superheated operation with the addition of Caprotti valve gear, resulting in their reclassification as Class 625 locomotives. Their numbering system was adjusted by replacing the initial digit with a '3' while maintaining their original sequence—for instance, engine number 600 008 was renumbered as 625 308. Following these conversions, the remaining unmodified Class 600 locomotives—numbering approximately 95—were progressively retired and scrapped after 1933.

Operation

File:Targa FS 625116.jpg

FS 625.116 numberplate

These locomotives were engineered for dual-purpose use, suitable for both passenger and freight services, and specifically built to handle steep inclines. The initial units of this class entered active service upon their completion in 1910, with the last locomotives being retired from mainline operations in 1976. Several members of the class were maintained in a preserved operational state as part of the Italian Railways' strategy to keep steam engines on standby, even during the dominance of diesel and electric traction. The final locomotive removed from this reserve status was unit 625 100 in 1998.

Class 623 conversions

During the early 1950s, thirty-five class 625 locomotives—including ten that were originally rebuilt from Class 600—underwent conversion into class 623. These units were equipped with the Franco-Crosti boiler, characterized by two pre-heaters mounted alongside the main boiler, giving them a distinctive appearance. However, this design proved unsuccessful, leading to the complete withdrawal of these locomotives by the early 1970s, with none preserved.

In popular culture

Italian model manufacturer Rivarossi has produced several scale replicas of the class 625 locomotives.

Locomotive number 625 116 was featured in the 2013 Italian film The Magistrate, directed by Giulio Base.

Locomotive 625 017 has drawn interest due to its service on the Vatican Railway, which is unique as the only national railway without its own locomotives. This engine pulled a train for Pope John XXIII in 1962 and later, in 2015, operated the inaugural run of Pope Francis's weekly train journey from Vatican City railway station to Castel Gandolfo. The same locomotive has also been used to transport members of the Italian royal family.

Preservation

File:625-177 2.jpg

Preserved 625 177 on an enthusiasts' charter train.

A total of twenty-five Class 625 locomotives have been preserved; among them, units 625.100, 625.116 (held by a private museum), 625.142, and 625.177 remain operational and are available for heritage rail services.

Notably, locomotive 625.308 is the sole surviving FS engine fitted with internal Caprotti valve gear and is currently undergoing restoration in Pistoia.

External links

• Technical drawings of the FS Gruppo 625 locomotives (Archivio Fondazione FS Italiane – www.archiviofondazionefs.it)