Eau-la-la! What could be more romantic than falling asleep on the gently rolling Seine? This lovely 100-year-old houseboat, docked at Port de Suffren, floats under the shadow of the Eiffel Tower and offers spectacular 360-degree views from its private deck. The split-level studio apartment is quite cozy, making it ideal for a couple looking for a chance to get really close. From $172 per night at Airbnb.