Arc de Triomphe du Carousel

Located between the Tuileries and the Louvre courtyard, and built between 1806 and 1808 to commemorate Napoleon’s military victories in the Wars of the Third and Fourth Coalitions (so saith Wikipedia). Its rather bigger and more famous sibling at the far end of the Champs-Élysées, properly known as «l’Arc de Triomphe de l’Étoile», was designed the same year but not finished until 1836.