The blowing up of the bridge in "The Pride and Passion" (1956) is a very interesting "unknown" scene.
It was shot with the best daylight, but the entire scene was converted artificially into a night scene. 
In the movie very little can be seen of the scene.
There are several possible reasons.
One reason is surely the great danger for all involved (Extras, Horses,...).
The Explosion of the Bridge is marvellous big bang!
We will show you what really happens during the blowing up of the bridge.
The photo above shows a Storyboard sketch of the scene.
The responsible Art Director for "The Pride and Passion" was Fernando Carrere together with Gil Parrondo as Assistant.
The Bridge Set was built by Francisco Rodriguez Asensio and his Team (Asensio Construcciones Cinematograficos S.L.). 
All photos are of my archive - Photos made by Ken Danvers to document the scene for Stanley Kramer Films.

Rio Tajo 1956 - So many Extras on a rickety bridge. Something will happen!

Bang! - Wow! - Look at all that wood in the air. And this is just the first Explosion...
German Lobby Card - Photo by Ken Danvers.
Halleluja...they are crazy! - The life of an Extra is not always easy!
S.O.S. - Save our Souls - There were certainly a few injuries!
Jesus...look at the guys. Some drift in the water, while others are on the remains of the bridge.
The guy next to the cannon staggers around...
Another close view. Horses in the water...the guys on the bridge don't look comfortable.
A rescue boat is coming. Many people in the water.
Anyone who falls into the water with a full costume quickly comes into problems.
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Many people floating in the Rio Tajo, a few horse and lots of wood.
There is not much left of the bridge...a very dangerous scene.
This crazy guy is jumping back in the water! - Perhaps he has discovered his hat...
A horse is rescued.
A second boat is coming to save the people...and their costumes!
There are still people in the water. 
Hopefully someone has counted the guys at the end and all are resurfaced.
"The Pride and the Passion"
In a break during filming: Carlos Larrañaga, José Nieto, ...
The Cannon is drifting on the Rio Tajo.
At the end of filming in Spain at least one Cannon flew back to America.
The cannon was shown in the Saint Augustine Jail (museum) in Florida.

Hollywood in Spain

 www.movie-locations-spain.com