For a few Saturdays each year, the NYC DOT shuts down car traffic on several streets across the five boroughs. It's called Summer Streets, and from around midnight until around 2pm you'll find only pedestrians and bikes on these stretches of road. I recorded this from the median of Park Avenue as bike traffic zipped by.

https://www.nyc.gov/html/dot/html/pedestrians/summerstreets.shtml