Square du Vert Galant
Ile de la Cité, 75001 Paris

The River-Level Picnic: I highly recommend bringing a baguette and some local cheese for a sunset picnic at the very western tip of the square; it is one of the only spots in central Paris where you can sit right at the water’s level and enjoy an unobstructed view of the river and the passing boats framed by the arches of the Pont Neuf.
The little Vert Galant Square is located at the western tip of the island.
A small green space with a few trees, it makes for a charming viewpoint of the Seine and its banks, bridges and monuments.
The imposing equestrian statue of Henri IV reminds visitors that it was he who first took the initiative to develop the western tip of the Ile de la Cité into a residential area.
My Tip: To see the medieval highlights, this is the experience I suggest.