Even on a tight schedule, Seine Bridges & Quays Walk earns the hours.
Allow 1.5–2 hrs.
Strolling the Seine quays past the Pont Neuf, Pont des Arts and Pont Alexandre III, with booksellers' green stalls and bridge-framed Eiffel views, is the cheapest great thing to do in Paris. Best at golden hour; the riverbanks are a UNESCO World Heritage Site.