A single 3–4 hour ride strings the Eiffel, Notre-Dame, the Louvre and the Champs-Élysées into one loop — the best-value way to get your bearings on a first day, now that Paris has built out real protected bike lanes. The operator-level call: Fat Tire (Unlimited Biking) near the Eiffel runs the big, English-language small-group tours and the well-known night ride; Blue Fox Travel is the more boutique, family-friendly alternative. Day tours win for orientation; the after-dark ride wins for romance, with illuminated monuments and far less traffic — but the whole thing lives and dies by the forecast.