The large yellow signal lit up the building after Mayor Eric Garcetti, LAPD Chief Charlie Beck and Burt Ward, who played West's Batman sidekick Robin, paid tribute to West with funny speeches.
"My friend Adam would want every single one of you to be incredibly happy and to be joyous because he spent his entire life as a performer making people happy, making them laugh and trying to make this world a better place," Ward said.
Thousands of people gathered in front of City Hall wearing Batman costumes, shirts and other attire. The Batmobile, which West drove in the 1960s "Batman" television show, was on display during the ceremony.
West lost his battle to leukemia Friday at the age of 88. He was best known for his portrayal of the Caped Crusader. He also lent his voice to characters on "Family Guy" and "The Fairly OddParents," among other shows.
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