"It's very hard for us to accept that she's no longer with us," said vigil organizer Liset Ortiz.
Rivera, who starred in the popular musical television series 'Glee,' died nearly three weeks ago in what authorities determined was an accidental drowning.
Naya Rivera update: Officials release cause of death after body found at Lake Piru
The 33-year-old actress took a boat out on Lake Piru spending an afternoon with her 4-year-old son. Later that day, her son was found alone in the boat. Days later, searchers found Rivera's body in the lake.
Heartbroken fans say they admired Rivera as a person and as a performer. Many of them identified with the character she played on glee.
"With the help of her character, she helped me accept myself for who I really was and I was more open with my sexuality," said fan Kimberly Martinez.
"Santana, her character on Glee meant a lot to the LGBTQ+ community. She was a great actress, a great person, a great mother," said fan Christina Saunders.
WATCH: Surveillance video shows Naya Rivera, son at Lake Piru before her disappearance
Balloons were released over the lake as a final tribute.
"She taught me how to be myself and be unapologetic about it," said Ortiz.
"This is a way for us to say goodbye to her. Not just us but a million, thousand people on Twitter, Instagram, are all here with us."
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