At the very western fringe of the 12th arrondissement, you will find possibly the quaintest, most beautiful street in the entire city of Paris:
The street itself is relatively short, pedestrianised and cobbled with stunning, brightly coloured houses lining both sides. During the short journey along the street you might see antique bicycles chained to downpipes, ivy (both real and painted) overhanging doorways, real cats in windowsills and painted cats jumping between windows, cane birdcages with canaries and a multitude of pot plants and trees.
Rue Crémieux. It's a hidden treasure in the Parisian sprawl.