One and half year producer Wolper had searched for a bridge that resembled the Ludendorff Bridge on the Rhein at Remagen. The Davie Bridge in Czechoslovakia does not look much like its historic predecessor but it was the best Wolper could find. Due to the political climate in Czechoslovakia during the Dubcek era an American film crew was very welcome. Officials were hoping for western contact and money. The Czech government agreed with Wolper on Czech soldiers as extras, playing American and German soldiers, and even stopped the traffic on the river for the time of the shooting American uniforms and weapons could easily be rented at American and West European costume rentals, whereas German uniformas and weapons were available on location, since they were used in many Czech films about the home resistance fighting nazi occupation forces. Tanks and other heavy equipment were rented from the Austrian ministry of defense which had purchased the vehisles as a war surplus from the US after WWII.
After two thirds of the film had been shot, production had to be stopped since Russian troops had invaded Czechoslovakia to topple the Dubzek government for its too liberal politics. A fleet of taxis was rented on August 22nd to take the crew the Austrian border. In Vienna, Wolper negeociated with the Russian general about returning the tank and the rest of equipment left behind. Shoting was continued in Austria, Germany and Italy, where a new bridge was build near Castel Gondolfo. A second unit returned to the bridge at Davie, where they filmed the long shots with the tanks, armor, and Czech soldiers as extras, this time performing under the watchful eye of the Russian Army.
Filmed on location in Czechoslovakia. The last part of filming was interrupted by the 1968 Russian invasion of Czechoslovakia and had to be completed in Austria. The crew even constructed half a bridge replicating the one they were forced to leave behind.