Sir Sean Connery once described this movie's location work as "the most audacious piece of filmmaking I've ever been involved in. It was film production at the point of pioneering." Connery once recounted the worst moment he experienced while making this movie. Connery had to make a three hundred meter (three hundred twenty-eight yard) walk alone down a glacier known to be laden with crevasses hidden by a fresh snowfall and without safety markers. The marker poles were present during rehearsals, but were not there during filming, as they would be seen in the shot. Connery said, "Inches on either side of the path there were ninety foot caverns. I could hear the sound of ice moving underneath me, and behind me in the peaks, shifting all the time. That's the loneliest walk I've ever taken."
The movie was a critical and commercial failure at the box office. Producer and director Fred Zinnemann said: ""I'm not saying it was a good picture, but there was a degree of viciousness in the reviews. The pleasure some people took in tearing down the film really hurt."
Head mountaineer guide Andrea Florineth's advice and warning to the cast and crew was, "If you fall, you must at all costs try to keep awake, because if you sleep, you'll never wake up again."
Of this mountain movie, producer and director Fred Zinnemann once said of the mountains he experienced in his youth in Austria-Hungary (now Austria): "I loved the feeling of one had in those old days of going to a place that was absolutely still, the silence, the feeling of majesty, the mystery."
The source short story "Maiden, Maiden" by Kay Boyle was first read by producer and director Fred Zinnemann about thirty to forty years earlier. He said: "A story which has haunted you for so long has done so for a very good reason. I have never been able to get the shape of the tale from my mind. The coming together of this haunted love affair amidst the purity of the Alps has sure and certain correspondences for me."