In March of 1953, the Academy Awards were televised for the first time, which also marked the first time the ceremony was being hosted simultaneously in Hollywood and Manhattan—an experiment that carried on through 1957 before being abandoned. In part the bi-coastal broadcast was an effort to bring the award show to the actors who were committed to Broadway shows, unable to leave the city.
In New York, the 1953 ceremony was hosted inside of the NBC International Theatre in Columbus Circle, which was demolished the following year. (It was sitting in the spot where the Time Warner Center is now.) While the east coast event was being hosted by Conrad Nagel and Fredric March, over in California Bob Hope was steering the ship—here's his fantastic opening, where it's briefly mentioned there's some other alternate universe over in New York hosting a dual ceremony:
And here's Shirley Booth winning for Best Actress (for "Come Back, Little Sheba")—she accepts her award at the New York ceremony... but not before a classic trip up the stairs:
In 1954 the New York ceremony was moved to the New Century Theatre on 7th Avenue and West 58th Street. The Bowery Boys note that "film fans were set up in bleachers outside, just as they're popularly done out in Los Angeles. But one New York nominee didn't get there in time to meet her fans. Audrey Hepburn was down at the 46th Street Theatre performing the play Ondine, costumed in a blonde wig. After the show, she raced to the Century in a limousine (with police escort, no less), ripped off her wig, rushed to bathroom to wipe off her stage makeup, then settled to her seat for less than ten minutes before standing again to accept the trophy for Best Actress for Roman Holiday." Here she is accepting her statue by giving a delightfully brief speech (and here's a LIFE magazine article with photos of her getting to, and at the ceremony).
Click through for a look at the New York ceremonies over the years (below is some back-and-forth between LA and NYC in 1955). After 1957, New York's co-hosting duties were over, and the ceremony has been held solely in Los Angeles ever since.