Contemporary news items add the following information about the production: RKO purchased James Ramsey Ullman's novel in Mar 1946 for $150,000. At that time, Edward Dmytryk was assigned to be the film's director, and Ullman was to work on the script. Credited writer Paul Jarrico's first draft of the screenplay, which was completed in early Apr 1947, reportedly eliminated the "allegorical implications of the novel," because they were deemed "no longer valid." These "nationalistic allegories of the war period," however, were present in the final draft of the script. Ullman's contribution to the final screenplay has not been confirmed.
       In Jan 1947, Lilli Palmer was announced as the lead in the production, which was to begin in Switzerland in Jun 1947, following six months of research and preparation. L. P. Williams was assigned as art director at that time, William E. Watts as executive production assistant, Ruby Rosenberg as Dmytryk's assistant, and Ullman as technical advisor. By Apr 1947, however, "upset conditions in Europe" caused principal photography to be postponed, and RKO announced in mid-Apr that the picture was to be filmed in the Canadian Rockies and Hollywood. On 14 Apr 1947, RKO sent Dmytryk, art director Alfred Herman, cameraman J. Roy Hunt and location director Lou Shapiro to Calgary and the Canadian Rockies to do tests. By 21 Apr 1947, however, the studio declared that it was shelving the project for at least a year because of casting difficulties, labor problems in Switzerland and the release of Monogram's High Conquest (See Entry), another mountain climbing film. (Although both High Conquest and The White Tower predated Sir Edmund Hilary's scaling of Mt. Everest by a few years, mountain climbing had become a very popular pursuit after the war.) Var also reported in Sep 1947 that the Canadian Rockies had been ruled out as a location because they were not "sufficiently similar" to the Alps. Paul Lukas was slated for a starring role in the picture during its 1947 production tenure. Of the above-mentioned crew members, only Ruby Rosenberg has been confirmed as contributing to the final film.
       RKO did not resurrect The White Tower until mid-1949. While the project was on the shelf, Dmytryk and his RKO collaborator Adrian Scott were indicted for contempt of Congress during the HUAC hearings and were fired by RKO. (For more information about Dmytryk and Scott's involvement with the HUAC, See Entry for Crossfire.) Irving Allen and Franchot Tone, producers of The Man on the Eiffel Tower (see above entry), a 1949 RKO release, were then set to produce the film. Rudolph Maté was to direct the picture in the southern Alps, with Tone, Glenn Ford and Oscar Holmolka in the cast. By 23 Jun 1949, however, Ted Tetzlaff had taken over as director, and M-G-M contract player Janet Leigh was announced as the film's new star. Also in late Jun 1949, photographer Richard Angst and production designer René Renoux were hired to work with credited Swiss cinematographer Tony Braun on the picture, which, at that time, was to be shot in Switzerland in Ansco Color.
       On 28 Jun 1949, John Garfield was announced as Ford's replacement and Valli, as Leigh's. Ford had reportedly accepted the part on condition that Leigh also be cast, and when Leigh's loan-out deal with M-G-M fell through, Ford backed out of the picture. Despite the loss of Leigh, Ford returned to the project the next day, but pulled out again a week later because of a salary conflict. During Ford's absence, Tone stepped down as co-producer, and Mel Ferrer was announced as Ford's possible replacement. Irving Allen was to stay on as supervising producer, but his contribution to the completed film has not been confirmed. In mid-Jul 1949, just before the film crew, led by Technicolor photographer Ray Rennahan, was to leave for France, Ford was re-signed at a salary of $125,000. Valli was to receive $75,000. In late Jun 1949, Richard Basehart was announced as a cast member, but did not appear in the completed film. Although HR stated that Valli was to be billed using her full name--Alida Valli--for the first time "in several years," her onscreen credit remained "Valli."
       Second-unit filming, which consisted of trained climbers and doubles, was done in Chamonix, just north of Mont Blanc, France, the highest peak in the Alps (15,781 feet). Principal photography was also done in the French Alps, using Eastman Mono-Pack color instead of Ansco, and at RKO-Pathé studios in Culver City, where Technicolor stock was employed. For the studio filming, a mountain set was constructed. Mountain and snow photographer Andre Roche was to do stills for the picture, but his contribution to the final film has not been confirmed. It is not known if any of the Canadian background footage was used in the completed film.