In 1946, the statewide chain of 110 Golden State/T&D Theaters wanted a state-of-the-art Cycloramic screen in Santa Cruz. It created a three-dimensional illusion of depth (independent of any 3-D film processes which had yet to be developed) and gave added clarity to the picture, with no distortion from close-up seats. But its curving shape couldn't be raised and lowered like the flat screens at their two local theaters--the Del Mar and New Santa Cruz--which would render their stages unusable. This was unacceptable for the pair of combined cinema/stage/convention theaters called "the king and queen of Santa Cruz movie palaces." So Golden State built the Rio Cycloramic Theatre, and located it in the booming East Santa Cruz business district, also called "downtown Branciforte." Some think the theater was dubbed "Rio"("river") for the Spanish town named after Branciforte Creek, or as "the theater beyond the [San Lorenzo] river." But it's just as likely its ocean liner-inspired architecture suggests a steamship cruise to Rio de Janeiro, a tropical destination reminiscent of Santa Cruz. Construction ran from 1947 to 1949. The Rio was built of Davenport-area cement and Hebbron-Nigh Lumber; with the ticket booth, aluminum doors and poster cases crafted by Modern Industries of Oakland; the chairs, carpets, drapes, and projector from National Theater Supply; and lighting fixtures from Peerless Electric of San Francisco. The 938 seat Rio opened June 12, 1949, with a live radio broadcast on KSCO of the 15-minute dedication ceremony. Then theater patrons enjoyed a double feature of "Song of India" and "Law of the Barbary Coast."