Parc Monceau
Parc Monceau is a little gem of a park I stumbled into the first morning I ever walked around Paris and now I visit it at least once every time I go. You’re going to see plenty of dogs, ducks, Parisians exercising, and older Asians doing Tai Chi. It’s a beautiful spot with gardens, ponds, a pyramid, bridges, a Dutch windmill, columns, a Chinese Fort, and statues of famous Frenchmen.
It was created moments before the Revolution in the 1770s by Phillippe d'Orléans, a French Duke who was a lover of all things English which is why this Parc Monceau is modeled after the English Gardens of that era. That English Garden aspect sets this park aside from pretty much all other parks in the city (like the Luxembourg Gardens) which makes it worth a visit.
Monet painted quite a few of his works at the park! The park also used to feature quite a few more buildings and artworks but the dirty communards of the 1871 Commune burned them down.
Just outside the Park, due south, is a very cool building known as Pagoda Paris.
Nearby: Palais Garnier, Arc du Triomphe, Petit Palais