Salamanca dam used in Schwarznegger's 'Terminator 6'

The ravine in Aldeadávila which houses a lock owned by electricity board Iberdrola for producing hydraulic energy, part of the river Duero and in the middle of a nature reserve, will see around 200 cast and crew members descend on it, of whom around 20 are from Aldeadávila and will be working as extras or taken on for a few days to work behind the scenes.

Some of Iberdrola's hydraulic power station staff on the site will be among the extras.

A dramatic series of scenes against a dramatic backdrop, the part of the latest in the Terminator series shot in the dam will involve high-speed cameras and drones.

It is now 26 years since the Terminator 2 was thrust into the unusual situation of being a sequel more famous and popular than the original production, hurling Schwarznegger into the global spotlight and adding expressions like “I'll be back,” and “Hasta la vista, baby,” to common speak.

Since then, Schwarznegger has been governor of the State of California, but he is due back in his leathers, 'fleshing' out the molten-metal-cored mechanical hero, under the auspices of director James Cameron.

For the Aldeadávila canyon – 140 metres high, 250 metres wide and able to hold up to 115 cubic hectometres of water in a 368-hectare (909-acre) space, the equivalent of nearly 97 football stadia – all this is old hat, however.

As well as the Spanish film La Cabina ('The Cabin'), the Salamanca dam was one of the locations for the classical screen adaptation of Boris Pasternak's Russian Revolution novel Doctor Zhivago, starring Omar Sharif as Yuri Zhivago and Julie Christie as Larissa, which won five Oscars and five Golden Globes.

When not gracing the silver screen, the Aldeadávila dam operates as one of Spain's largest electricity generators, creating over 10% of the country's hydraulic energy – enough to fuel a quarter of a million homes – whose mere presence and use reduce annual CO2 emissions by 1.3 million tonnes.