The Frecciarossa from Roma Termini to Napoli Centrale takes around 1 hour 10 minutes, running multiple times per hour through most of the day. Book in advance on Trenitalia; advance fares are significantly cheaper than walk-up prices, and the high-speed trains fill up on Monday departures. Arrive at Napoli Centrale, and you are immediately in one of Italy's most caffeinated cities.
Naples is an acquired taste and a genuine one. The traffic is loud, the streets around the station are dense with commerce, and the centro storico is simultaneously magnificent and chaotic. Spend Monday recovering and eating. Tuesday, go to Pompeii or Herculaneum.
Naples: Day One
The Museo Archeologico Nazionale di Napoli is the single most relevant pre-Pompeii stop in Italy. The artefacts removed from Pompeii and Herculaneum, including the Alexander Mosaic, the Gabinetto Segreto's collection of erotic art, and hundreds of items from both sites, are here rather than on site. If Pompeii is on the itinerary, visiting the museum first inverts the usual expectation and makes the city more comprehensible rather than less. Tickets approximately €18; allow two to three hours.
For food on the first evening, Naples invented pizza as it is understood internationally, and the pizza here is different from every imitation. L'Antica Pizzeria da Michele on Via Cesare Sersale makes only two pizzas, Margherita and Marinara, and has been doing so since 1870. The queue is part of the experience; expect 30 to 45 minutes on a Monday evening. Budget alternatives with shorter queues include Sorbillo on Via dei Tribunali. For something beyond pizza, the Spaccanapoli area (the long diagonal road that cuts through the historic centre) has trattorias serving pasta e fagioli, friarielli, and whatever the kitchen decided was good that morning.
Pompeii
The Circumvesuviana commuter train from Napoli Piazza Garibaldi (adjacent to Napoli Centrale) reaches Pompei Scavi station in around 35 minutes and runs throughout the day. Buy tickets on the day from the station; these are regional trains and advance booking is not necessary.
Pompeii is large. The site covers roughly 66 hectares, and a thorough visit takes five to six hours on flat, even-surfaced ancient roads. That is more walking than tired marathon legs need, so a selective visit focusing on two or three areas is a better strategy. The Lupanare (ancient brothel), the Triangular Forum, the Villa dei Misteri (outside the main walls, worth the walk), and the House of the Faun repay a focused hour each.
Herculaneum (Ercolano on the rail line, one stop before Pompeii) is more compact and better preserved, because it was buried by pyroclastic flow rather than ash. The site is manageable in two hours and involves less distance on recovering legs. For runners who want Vesuvian history without a full-day commitment, Herculaneum is the practical choice.
Tickets for Pompeii: approximately €18. Herculaneum: approximately €15. Combined tickets and timed entry slots are available at pompeiisites.org; booking in advance is advisable in April.
Getting Back
Frecciarossa trains from Napoli Centrale to Roma Termini run throughout the afternoon and evening. The journey is the same 1 hour 10 minutes in each direction. Book the return at the same time as the outward leg; prices firm up significantly as the departure date approaches.