The Luxembourg Garden is one of the largest green spaces in central Paris, covering 23 hectares, or 57 acres. (Trivia for me: that makes the Luxembourg Garden 100 times the size of the piece of land we live on near Saint-Aignan.) You get great views of the garden and palace from the top of the nearby Tour Montparnasse.
In the photos above and below, you can see many of central Paris's main monuments and sights. On the upper left is the Centre Pompidou, a modern art museum, library, and cultural center. Toward the top center is Notre-Dame Cathedral. On the right are the dome of the Pantheon and the modern tower in the center of the Jussieu university campus. (Click or tap on the photos to enlarge them.)
Just outside the eastern gate of the Luxembourg Garden is the Latin Quarter. The Luxembourg Palace, on the north side of the garden, is the seat of the French senate. The palace was built between 1615 and 1645 to serve as the royal residence of Marie de Médicis, who was the mother of the young king Louis XIII and his regent. The Luxembourg Museum is also located in the park.
I've taken and posted photos of the Luxembourg Garden and Palace several times before. See these posts from August 2013 and September 2009, among others. You used to be able to take a tour of the Senate chambers when the body wasn't in session. Maybe you still can. I did it once, and I was allowed to sit in Victor Hugo's seat for a minute or two, if I remember correctly.