THE VEHICLE AT A GLANCE
Model dossier
- Manufacturer
- Alfa Romeo
- Base model
- 6C 2300 Gran Turismo
- Coachbuilt version
- Cabriolet Royal
- Coachbuilder
- Castagna
- Production period
- 1934
- Body style
- Cabriolet
THE PEOPLE BEHIND THE CAR
Coachbuilding, design & conversions
PRICE & SALES RECORD
Vehicle value
- Original price
- Not documented
- Latest recorded sale
- Not documented
01 / THE STORY
History & context
The Alfa Romeo 6C 2300 GT Cabriolet Royal, bodied by Carrozzeria Castagna and built on chassis no. 700.212, was completed in 1934. It is the only known example of its type, constructed on the first series 6C 2300 Gran Turismo chassis, and presented publicly at the 1934 Milan Motor Show. This car was designed as a demonstration of both the technical capabilities of the newly introduced 6C 2300 and the refined coachbuilding tradition of Castagna. The chassis employed was part of the 6C 2300A series, featuring a 2,309 cc inline-six engine with dual overhead camshafts and hemispherical combustion chambers. In its original configuration, the engine produced 68–76 horsepower, depending on carburetion. Chassis no. 700.212 was later fitted with a pair of Solex twin-choke carburetors and a dedicated intake manifold, increasing output beyond factory figures. The drivetrain included a four-speed manual gearbox and rear-wheel drive. The car utilized rigid axles, semi-elliptical leaf springs, and mechanical drum brakes. The body was constructed in the Royal Cabriolet style, a term used by Castagna to denote a particular luxury cabriolet configuration with a high waistline, full-length doors, retractable soft-top with articulated frame, and chrome embellishments. The car was configured as a four-seater, with enclosed rear passenger space and detachable side windows. The dashboard was finished in machine-turned alloy, with Jaeger instrumentation and Castagna’s identifying plaque. Chassis 700212 was exported to Argentina shortly after completion, where it was registered in the Buenos Aires province. Rediscovered in the late 1970s, it was repatriated to Italy around 1980 and subsequently restored. It has been recorded in the possession of private collectors and has participated in multiple historic motoring events, including the Targa Sanremo and RIAR (Registro Italiano Alfa Romeo) meetings. Only one example of the 6C 2300 GT Cabriolet Royal by Castagna is known to have been built.
02 / TECHNICAL IDENTITY
Specifications & construction
Production & construction
- Production type
- One-off
Engine & performance
- Engine configuration
- Inline-6
03 / DESIGN, BODY & SUPPLIERS
Design, body & suppliers
Design & manufacture
- Manufacturer · Documented
- Alfa Romeo
- Coachbuilder / Body Builder · Documented
- Castagna
Body form & construction
- Body style
- Cabriolet
04 / EVENTS & CHRONOLOGY
Events & chronology
No events or documented awards are currently recorded for this vehicle.
06 / CHASSIS REGISTER
Chassis register
Chassis 700212
Identification & build
- Chassis number
- 700212
- Model year
- 1934
08 / GALLERY
Photo gallery 9 photographs
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09 / PERIOD ARCHIVE
Period photographs & advertising
The period archive gallery will show historical photographs, advertisements, brochures and press images once assets, provenance and usage rights have been recorded in the masterfile.











THE CONVERSATION
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