This square bears the name of a prefect of police who established a competition for amateur inventors in 1902. A lesser-known fact is that Louis Lépine was also responsible for the rules of the road and for creating the police officer corps. To the north of the square, the Seine adds a feeling of openness to the flower market, which is surrounded by austere public buildings dating from the Second Empire period. On Sundays, the flowers are replaced by birds.