Arts et métiers is one of the most original stations in Paris. It is set as if you were inside a submarine, in a steampunk vibe and reminiscent of the tales of Jules Verne.
It is clad in copper and has portholes containing models of various historical machines. Even at the top of the vault there are giant metal gears. This is because it is located next to the National Conservatory of Arts and Crafts, and they made a nice tribute.

The Châtelet-Les Halles station is one of the largest I've ever been to, whenever I pass by it I get lost and a little anxious.
Three RER lines (connecting trains to suburban areas) and five lines of the Paris metro pass through there. It is located under the Forum des Halles, the largest subway shopping mall in Europe.
It has several floors and is always very crowded, which gives rise to my next series of illustrations.

The Franklin D. Roosevelt station on line 9 owes its name to the former U.S. president, named after the end of World War II. It is located under the Av. des Champs-Élysées, just where the gardens end and the luxury stores begin.
It has a decoration that automatically transports us to the 50's, with windows that functioned as showcases of products of the stores near the station.

This is the Cité station, which is located on the Ile de la Cité and is close to the Sainte Chappele and Notre Dame Cathedral. It's located at a depth of more than 20m, and was the first line to pass under the Seine River.

Line 6 of the Paris metro goes from Nation station to Etoile-Charles de Gaulle (Arc de Triomphe). In the middle it passes over the Seine river by the Bir-Hakeim bridge where you can see the Eiffel Tower this way.
The tower really impresses, but the amount of tourists around is even more impressive.