John Lennon's 70th birthday may have come and gone with quite the hullabaloo, but a rumored 20,000 New Yorkers spent the day celebrating the musician's legacy at Central Park.

With a little help from the city of New York, Lennon fans enjoyed a free screening of the new American Masters documentary "LENNONYC" Saturday night at Central Park's Rumsey Playfield. The documentary, which chronicles Lennon's New York residency from 1971 to his assassination in 1980, kicked off with an introduction from a another famous New York musician, Lou Reed.

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"To write something as moving as 'Mother' and 'Jealous Guy' is reason enough to be inducted into a hall of great songwriters," Reed told the thousands of New Yorkers who turned out to see the film, adding that Lennon was akin to a New York landmark.

While thousands were admitted to the "LENNONYC" screening, thousands more celebrated Lennon within the park's confines, whether it was watching the movie from behind the gates, or singing his songs near the "Strawberry Fields" memorial. Lennon's spirit was fully felt in Central Park that night.

Yoko Ono did not attend the screening, as she was in Iceland presenting the LennonOno Grant for Peace Award, but she sent a video message, which played before the film. "I know John would not have expected so much love to come from you, but he would have been very happy to know it," she told fans.

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"LENNONYC," which will air nationwide on PBS on Nov. 22 at 9pm, features a slew of unseen concert footage and unheard in-studio recordings, making the biographical film engaging for even the most well-informed Lennon fan.