Goofs

During one scene at an enemy check point, the night sky is full of stars (2:23:55). We see a mounted enemy patrol riding by the check point under the moonlight (2:24:02). A few moments later, outside is clearly daylight (2:24:45), yet when the enemy soldier inside the check point booth blows into the lamp (2:25:29), the booth is in total darkness and there is no daylight coming through the windows.

(around 1 hour, 28 minutes, 15 seconds; first scene after intermission) When Robert was hiding in the snow his hat became wet and covered with snow. He managed to shake most of it off however a few flakes remained. But on the next shot when he spots a trooper, the hat has no snow on it and it is dry.

Pilar and Pablo use an 1892 Krag-Jorgenson (or variant). Whilst it is possible, since the Spanish Civil War was called by one historian "A gunrunners paradise where they sold every type of firearm to the Loyalists", it is extremely unlikely that such a rifle, with its odd cartridge, was imported into Spain for the war effort.

Jordan plants the dynamite about 1/3 the way across the bridge span. But the actual explosion later comes right in the middle of the bridge, nowhere near the dynamite.

Early in the film when Gary Cooper's character Robert Jorden meets General Golz, Cooper's shadow can be seen on a wall in the background. In the straight-on angle, it's Cooper's shadow, but in another angle it's obvious another person was used to create the shadow. When Cooper places his hand on his chin, the shadow's move is late by a second.

(at around 50 mins) Pilar says "Wait" to Jordan and Maria. It is clear that the shot has been reversed, as the bolt handle and magazine on her Krag-Jorgenson carbine (see previous entry) was on the left of the rifle, whereas this weapon was only made in right-handed versions.

As one of the Loyalists is firing the Lewis gun on the mountain, you can see the bolt moving, but no shells ejecting.

On the dawn of the second day (at around 43 mins), as Jordan is waking up, a large metal fan can be seen spinning on the left.

Near the beginning of the film, when the bridge is viewed through binoculars, the angle of the view is often very inconsistent with Robert Jordan's position.