Before I got there, I hadn't known that you can actually go inside the Arc, climb up the inside & walk around on top of it. It's also bigger than I expected, though not as tall as the Eiffel Tower.

Paris is, interestingly, a very low city. While standing on one of the big monuments, you can see all of the others. Most of the tall buildings are not really in town, but all the way at one end of the Champs-Élysées. At that end of the road, there's a whole modern settlement and they built another, more modern-looking, arch. This arch is lined up perfectly with the Arc de Triomphe, which is, in turn, lined up perfectly with a smaller arch in a park at the other end of the Champs-Élysées just past the Place de la Concorde.
Just above & below you can see the entire length of the Champs-Élysées, as seen from the top of the Arc de Triomphe.

In Place de la Concorde, you can see the Ferris wheel and the beautiful Egyptian obelisk brought back to Paris by Napoleon Bonaparte. That big building behind the Ferris wheel is the Louvre! More on that later.