Complex sentence: It was also the site of the very first concert by The Beatles in the United States on February 11,1964, occurring on the same trip as the now legendary tapings for The Ed Sullivan Show.
Split into simpler sentences: It was also the site of the first Beatles concert in the United States on February 11,1964. This arena was the site of the first US concert by The Beatles, occurring on the same US trip after the now-legendary tapings for The Ed Sullivan Show.