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A taxi from NAP to Positano takes about 1hr 15min, and costs about €90. If traveling in a group, a private shuttle may be more cost effective, as some can transport up to 8 people for about €240. A more budget friendly option is a combination of buses and train from Naples to Sorrento. First from Naples Airport, you will take an Alibus to the train station, Napoli Garibaldi. From there, the Circumvesuviana train will take you to Sorrento. Finally, a SITA bus will take you to Positano. The total cost is €10. Travel time could range from 2hr 15min to 3hr, depending on the transfers.
Flight
Explore Rome before or after the wedding! From Rome's airport (FCO) to the Rome train station (Roma Termini), you can take the Leonardo Express train. It is a 30 min train ride for €14. You can buy tickets from machines at the station. There is a direct train from Rome (Roma Termini) to Naples (Napoli Centrale) that takes about 1hr 10min, for about €50. Check out this website for more information: https://www.italiarail.com/pages/routes/rome-to-naples.
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