On 1 May 1965, LAT announced that Gibraltar Productions had signed Rock Hudson to star in the Gene Corman production of Tobruk for Universal Pictures. Two days later, DV suggested that Alec Guinness was in talks for a supporting role, but he does not appear in the final film. Over the next few months of development, contemporary news items reported several title changes, including: The Cliffs, The Cliffs of Mersa, The Cliffs at Mersa, Hot Eye of Hell, and Destination Tobruk.
       The 28 Jun 1965 DV estimated a negative cost of $6 million, owing to a lengthy sixteen-week shoot in Spain, where Corman claimed they would have access to necessary period battle costumes. Around this time, the 8 Jul 1965 edition noted that Universal considered hiring director Ken Annakin, who was already in Spain completing The Battle of the Bulge (1965, see entry). A report in the 28 Feb 1966 DV revealed that a previous plan to film in Israel had fallen through due to the political climate of the region and the required cooperation of the Israeli Army. By the end of the summer, the 30 Aug 1965 LAT announced Universal’s intentions to move production stateside. Although no U.S. forces were involved in the Siege of Tobruk during World War II, the film unit received assistance from the California National Guard, whose gear was disguised as British and German.
       Principal photography began 20 Jan 1966 in Yuma, AZ, according to a DV news item published that day. All twenty-nine desert battles were expected to be shot in full Technicolor, without the use of any WWII stock footage. Filming also took place at the Salton Sea, a saltwater lake in Imperial County, CA, and the El Centro area just north of the California-Mexico border. The 24 Feb 1966 DV stated that director Arthur Hiller decided to relocate the principal cast to the Universal studios in Los Angeles, CA, while actor Nigel Green recovered from the flu. The following week, Green returned to El Centro for a final four days on location. Although the 25 May 1966 Var indicated that production had recently been completed, a DV brief two months later reported that re-shoots in Yuma had been delayed due to excessive heat.
       According to the 2 Feb 1966 DV, stunt pilot Frank Tallman returned to work overseeing aerial stunts on Tobruk after undergoing a leg amputation in 1965. A few weeks later, a 28 Feb 1966 DV report noted that actor Martin Kosleck had been hired as a German dialect coach, while University of California, Los Angeles (UCLA) professor Jivan R. Tabibian served as an Arabic advisor for some scenes featuring Hudson and more than 100 background actors hired to portray “Arab tribesmen.”
       News items in the 28 Dec 1965 DV and 19 May 1966 Los Angeles Sentinel indicated that Bobby Darin and Quincy Jones were both considered to compose the score—a job that ultimately went to Bronislaw Kaper. A 6 Jul 1966 Var brief named Don Record of Visual Arts as the artist responsible for creating the opening titles; however, his participation could not be confirmed.
       The 25 Jan 1967 Var stated that Tobruk would be shown “on popscale” at the Criterion Theatre in New York City beginning 8 Feb 1967. On 21 Feb 1967, LAT advertised the film’s Los Angeles, CA, opening that same day.
       Tobruk received an Academy Award nomination for Special Visual Effects.