Visit the Basilique du Sacre Coeur, then to Notre-Dame, sightseeing in the Ile DE la Cite and the Ile St-Louis.

巴黎-上午去巴黎北部圣心大教堂，下午去巴黎圣母院，游览斯德岛和圣路易岛。

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For a waterside stroll there are the banks of the Seine -- and a particularly good spot for a quintessentially Parisian picnic is at the eastern tip of the Ile St Louis, a natural island in the Seine.

BBC: The great outdoors in urban Paris