You'll enjoy the museums and churches in Downtown Le Havre. You might want to make time for a stop at Le Havre Cathedral or Le Havre Beach.
If you're spending some time in Le Port, Le Havre Beach and Catène de Containers are top sights worth seeing.
Though Sainte Marie - Saint Leon might not have many top sights, you can venture to the surrounding area to see attractions like Vauban Docks and Carré des Docks.
If you're spending some time in Anatole France Danton, Appartement Témoin and COTY are top sights worth seeing.
If you're looking for some top things to see and do in Mont Gaillard and surrounding area, you can visit Le Havre Beach and Vauban Docks.