Susan C.
Yelp
A small park with plenty of tall leafy trees, benches, and a central fountain, directly next to (south of) NYC's City Hall building.
While it's currently fairly close to the bottom tip of Manhattan, the park in colonial times was considered the northernmost edge of the city. Being thus, it started off functioning as locations for services relegated to the city periphery--livestock pastures 1653-1699, an almshouse 1736-1797, a debtors prison and execution site when the British controlled the area during the Revolutionary War 1756-1783. Once the park became adjacent to the current city hall built in 1803, it then hosted the city's first art museum 1818, and the southern tip of the park was sold to the US government to convert into a post office 1867, then torn down and converted back to park grounds in 1939.
Constructed in 1842, the original fountain in the park was named Croton Fountain after the then new Croton aqueduct from which water was pumped to run it. In 1871 it was replaced by the current smaller version, designed by Jacob Wray Mould, who also co-designed Central Park's Bethesda Fountain.
There are a number of permanent sculptures of historic figures in the park as well as temporary sculpture installations. Overall the park is quite clean and safe, probably due to its proximity to the nearby city offices and police presence.
Due to its proximity to the city building where marriages are performed, you'll often catch couples taking marriage photos here in the park--have come upon these special moments a couple times as I've randomly walked through.
Fun fact: the park has 243 mapped trees according to city park services.
For more info:
https://www.nycgovparks.org/parks/city-hall-park