You might think Columbus Park is an odd name for a Chinatown park, but as one of New York’s oldest neighborhoods, this area has had many incarnations, and the park itself has had various names, among them Mulberry Bend Park and Five Points Park. Only in 1911 was it officially renamed for the Italian explorer.
Today Columbus Park is regularly filled with Chinese people. Kids can play on a playground here, and there is a basketball court as well. On multiple occasions I have seen groups of Chinese men clustered intently around games at park tables.
I have also heard that you can find groups of people practicing tai chi in the park, and that you can—with respect, of course—join in for free.