Fast answer
Plan Cinque Terre without a car by making the train the default movement layer, then deciding whether the Cinque Terre Train Card actually fits the trip. Use La Spezia when arrival, luggage, price pressure, and repeated rail movement matter most. Use Levanto when a softer northern base and beach-town rhythm fit the stay. Use upstream cities such as Pisa, Florence, Genoa, and Milan as route checks, not guaranteed easy day-trip promises. Keep ferries, trails, Via dell'Amore, and visitor-flow rules as check-before-travel pieces, not fixed itinerary promises.
If you only do one thing
For a first no-car trip, choose the base first, then check the card against the actual days of train and trail use. Default to La Spezia for the simplest rail logistics, Levanto for a softer northern base, and a village stay only when sleeping inside Cinque Terre is worth tighter luggage, crowd, stair, and access constraints.
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