Highlights for me included the view of the NYC harbor from the area of the island known as The Hills. (The crowd of people in pink clothes were attending Pinknic, a rosé wine festival.)
Another part of the island I enjoyed was the small urban farm and composting center. I was happy to see birds that aren't pigeons.
There are also a couple of goats, and lots of plants, including vegetables and fruits. They're all labeled, as this is meant to be an educational farm. For instance, here's a display of different kinds of garden weeds (called the "weed library," which sounds like a collection of books best read when one is high):
Governors Island has some good play areas for kids too, like the giant slides, mini-golf, and this playground with climbing equipment (in the background, that's the Freedom Tower in Lower Manhattan).
There's also another playground made to resemble a junkyard (presumably without broken glass, syringes, and similar hazards - they even have some adult attendants, maybe to keep kids from getting stuck inside a tire or something).
On the one hand, kids often enjoy mucking around with discarded things, and the playground is supposed to push them to have fun outside the box maybe, no prepackaged play sets or toys. On the other hand, it's kind of depressing. Kids in really blighted, underfunded areas without playgrounds or community centers might find themselves playing in scrap heaps for lack of choice. This makes an organized recreational opportunity out of it.
Parts of the island are still under development (giving it a work-in-progress vibe that I like), though some of the old houses and buildings have already been put to use. Especially in Nolan Park, where there are summer residences for different arts groups and the Audubon Society. Castle Williams, an early 19th century fort, is another place worth visiting.
On to the second walk... this one started in Morningside Heights, at Columbia University, where we stopped at Alma Mater (statue of Athena by Daniel Chester French). She has an owl hidden in her robes to symbolize the effort of revealing knowledge.
We then walked east to Morningside Park (Carl Schurz Memorial Park), where the leaves and the light met just so.
It was Fourth of July, and many people were out picnicking and barbecuing. On the outskirts of the park is a replica of a statue of George Washington and the Marquis de Lafayette by Frederic-Auguste Bartholdi.
We headed into Harlem, down Morningside Avenue, then Convent Avenue. The City College of New York campus is worth visiting.
Don't miss out on seeing Shepard Hall, and the many grotesques that decorate the older buildings.
Grotesques are fantastical architectural decorations. (The ones that bear water away from the roof with a spout are gargoyles - which I didn't know, as I'd thought of all of them as gargoyles.)
Some of them look more mischievous, others more hideous or sorrowful. The one below looks like he's trying to find a polite way to answer a silly question.
Another highlight to the walk was Hamilton Grange, Alexander Hamilton's home.
There were a lot of lovely apartments to look at in the area.
We ended the walk around 150th street and St. Nicholas Avenue.