To truly experience the "gold standard" of the Italian Riviera, you should plan to spend at least three full days in Cinque Terre. While many day-trippers from Florence or cruise excursions try to see all five villages (Riomaggiore, Manarola, Corniglia, Vernazza, and Monterosso) in eight hours, this approach often feels like a frantic race between train platforms. With three days, you can dedicate one day to hiking the "Sentiero Azzurro" (Blue Trail) between the towns, another day to exploring the hidden side streets and vineyards of the more vertical villages like Corniglia, and a final day to relaxing on the beaches of Monterosso or taking a boat tour to see the colorful facades from the water. Staying overnight is essential because the villages transform after 6:00 PM; once the mass of tourists departs, the local atmosphere returns, allowing you to enjoy a quiet seafood dinner by the harbor. If you are an avid hiker or want to explore the "neighboring" hidden gems like Portovenere, extending your stay to five days will allow for a much deeper immersion into the Ligurian lifestyle and local wine culture.