 The extended scene following Berton as he rides back to the city was  filmed in Osaka and Tokyo. Foreign travel was not easily approved,  and the reason this long scene was left in the movie was probably to  justify that trip for the director and crew. A Japanese city circa  1970 may not look very futuristic to modern audiences, but its  impression on Soviet viewers at that time of the films release was  probably quite different. Tarkovskis diary reveals that they just  missed the Worlds Fair, and they may have planned to shoot footage  at it that would have looked far more futuristic.