Big, dirty, noisy, lively, vibrant, vital Naples is a double espresso city. It has you sitting bolt upright with your eyes wide open, your batteries recharged and your engine running. 'See Naples and die' has to be wrong. It must surely be 'See Naples and live'.

Tightly packed palazzos and tenements line the streets, with brightly coloured washing hanging between like crazy carnival decorations, every window flung wide to the tumult of the crowd. And what a tumult. Every conversation sounds like a confrontation; it's loud, lively and intoxicatingly theatrical.

But this constant clamour is only invigorating because of one ingredient: sunshine. If it were under the grey skies of London, Manchester, Birmingham or Edinburgh we would quickly tire of it. Under a blue sky and next to blue sea it becomes a tonic, a spring booster to blow away those winter blues, and cheap to get to now that Go, the low-cost airline, flies there direct from Stansted.

This is not really a tourist town. Don't expect to find another Florence, Venice or Pisa. The beautiful sweep of the Bay of Naples is dominated, yes, by Mount Vesuvius, but also by the huge docks which have been the city's lifeblood from the beginning. This is a working city, but that doesn't make it any less fascinating than those great 'living museums' further north. It gives it an edge and an attitude.

The Neapolitans are a proud, voluble, beautiful people - this is, after all, Sophia Loren's home town. Their city has a reputation for theft like none other in Italy, but I never felt threatened during my - admittedly brief - stay. You just have to be sensible: keep your money well hidden, don't wear anything expensive in the street and keep an eye on the constant stream of Vespas. They are a favourite with bag snatchers.

Neapolitans, in common with inhabitants of other poor cities all over the world, are superstitious and sentimental. The same shops that sell figures for ornate domestic nativity scenes also sell lucky charms to ward off evil spirits. They take their religion seriously, weaving it in to their daily lives. Churches are everywhere; step into any of them and you will find people of all ages stopping to say a prayer or the rosary, often with a bag of shopping at their feet. In the church of Gesu' Nuovo, Neapolitans queue to pay homage at the shrine of San Giuseppe Moscati, a doctor whose work with the poor in this overcrowded city led him to be canonised in 1987. They kneel at the feet of his effigy, holding its outstretched hand, kissing his tomb, offering flowers.

The city's historic palaces and fortresses are, of course, impressive and a must for any itinerary, but a morning walk down the unprepossessing Via Gregorio Mattei, off the Corso Umberto, will show you a piece of living history: the fish market near the docks. Octopuses struggle to wriggle out of tanks; live eels slither in buckets; great tuna stare blank-eyed at the sky, much as they have done for centuries in this bustling city of seafarers.

But bustling is hardly the word: frantic might be better. Ask anyone about their first impression and they will invariably reply 'the traffic'. Everyone seems to be in a desperate hurry to get somewhere, anywhere, either by car or by scooter. They drive right on each other's tails, run red lights, ignore pedestrian crossings and shout and argue when everything seizes up in the tiny backstreets.

They are, after all, a passionate people. Hear them in full cry in the audience at the San Carlo opera house. This beautiful theatre, second only to La Scala, Milan, with six tiers of white and gold boxes rising from floor to ceiling, resounds to their acclamations when the singers take their many curtain calls. We went to Verdi's Don Carlo: it began at a leisurely 8.30pm and finished at 1am. How very Neapolitan.

If you only do five things

1 Have a meal or a drink at one of the waterside restaurants by Castel dell'Ovo. Try Antica Trattoria da Pietro, via Luculliana, 27 (al Borgo Marinaro), Santa Lucia. It's cheap and cheerful and run by three generations of one family. A delicious bowl of mussels costs £2.

2 Take the Funicular di Montesanto (not to be confused with the Finicular Centrale) up to the Vomero district. Turn right through a black and yellow barrier, follow your nose to a T- junction and turn right. Be prepared for a stupendous view over the city to Mount Vesuvius. There are no signposts to this panorama, but it is truly wonderful. Enjoy a drink or a meal on the roof terrace at the Hotel Belverdere (Tel: 00 39 081 578 8169). V.T. Angelini 51, Napoli.

3 Visit the National Archaeological Museum for its extraordinary collection of exquisite frescoes and mosaics from Pompeii and Herculaneum. Stunning. Piazza Museo 19. 9am-7pm. Closed Tuesdays. Tel: 00 39 081 440 166.

4 Walk down the Via Toledo at 6pm, where the whole city seems to be out for the passeggiata, showing off their clothes and openly examining all the passers-by. Italians love to stare, so stare right back. This fine pedestrian street is lined with shops and palazzos, and filled with a constant, chattering, vibrant throng.

5 Spend half an hour in the peace and tranquillity of the Chiostro delle Clarisse at the Convent of S. Chiara . Decorated with blue, yellow and green majolica tiles and hung with wisteria, these cloisters are a peaceful haven away from the tumult of the streets.

Via S. Chiara 49/c. tel: 00 39 081 552 6280. Open 9.30am-1pm; 2.30pm-5.30pm (closes 1pm on public holidays). Entry 6,000 lira (£2).

Room for the night

Budget: Youth Hostel, Salita della Grotta a Piedigrotta 23, Mergellina. Tel: 00 39 081 761 2346. Out of the centre, but within reach by public transport. 30,000 lira (£10) per person per night.

Mid-range: Pinto Storey, Via G Martucci 72. Tel: 00 39 081 668 1260, 175,000 lira (£58). A beautiful wooden staircase and lift lead to the upper floors of this small hotel, established in 1878. Some rooms have panoramic views.

Luxury: Excelsior, Via Partenope 48. Tel: 00 39 081 764 0111. Around 500,000 lira (£154); suites up to 1,300,000 lira (£430). A truly grand hotel, all marble and stucco, standing on the seafront overlooking Castel dell'Ovo and the Bay of Naples.

Where to eat

Fast and filling: Naples is the home of the pizza, a cheap meal devised for poor families with only a few ingredients to spare. Try a calzone, a pizza folded over a libretto (like a book) and sold on the street all over the city for about 3,000 lira (£1). Delicious ricotta pastry puffs sell for a similar price, as do lemon rice balls dipped in breadcrumbs.

Good: The old-established Ristorante Transatlantico stands right by the water under the shadow of Castell dell'Ovo. Expensive yachts come and go. We ate smoked salmon and mozzarella, risotto al limone, and linguini alla Santa Lucia (an extraordinary seafood dish) with a bottle of Aspino, a local white wine, for 140,000 lira (£46). Ristorante Transatlantico. Centro Nautico Santa Lucia, Via Luculliana 15 (Borgo Marinari). Tel: 00 39 081 764 8842.

Totally sinful: The most famous restaurant in Naples is said to be La Sacrestia, which has breathtaking views over the bay. It's renowned for its fresh fish, aubergine ravioli and some elaborate deserts. Expect to pay above100,000 lira (£33) per head, with wine on top. La Secrestia, Via Orazio 116. Tel 00 39 081 761 1051. Closed Mondays.

Objects of desire

• Sweet tooth? Join the queue outside La Sfogliatella Mary in the Galleria Umberto 1, and buy amazing pastiera and babas for around 3,000 lira (£1).

• A ticket to the opera. Queue at the Teatro San Carlo from 10am for seats for that night's performance, or to book ahead.

Via San Carlo 98. Tel: 00 39 081 797 2331. Email for tickets at biglietteria@teatrosancarlo.it. The opera website is at www.teatrosancarlo.it.

• Italy's smartest designers are to be found in the Galleria Umberto 1, an impressive nineteenth-century covered gallery with a glass roof arching 187ft above the shoppers. Stores include Barbaro, outlet of the top Neopolitan designer, and Eboli, the jeweller. The principal street for elegant shopping is the Via Chiaia, near Piazza Plebiscito. Luise, in Via Martucci, sells Prada.

• Ice cream. Where would the Neapolitans be without gelato ? Find out by paying 3,000 lira (£1) for a little piece of heaven. You won't have to go far to find any. Try Baci, an ice cream version of the favourite Italian chocolate and nut sweet. You'll never be the same.

• Treat yourself to a Gambrinus, short or long, at the old café of the same name (Piazza Trieste e Trento). Pineapple, strawberry, orange and rum. It tastes best at 1.30am.

Behaving badly

Try the Via Bellini if you want some after-hours nightlife. There are three clubs to choose from:

Murat Liveclub offers Latin, 'breath guitar' and jazz/funk every night except Tuesdays. Via Bellini 8. Tel: 00 39 081 544 5919.

Latano da Dove claims to be a café, library, theatre and music venue. Entrance varies between 15,000 lira (£5) and 25,000 lira (£8.25) depending on shows. Via Bellini 3. Tel: 00 39 081 549 4304.

Bourbon Street offers a mix of jazz styles. Entrance free. Via Bellini 52. Tel: 00 39 347 051 2211.

Getting around

The traffic is so grim and the city so compact it's best to use your feet, but you can buy a Giranapoli ticket, valid on subways, buses and funiculars.

A 90- minute ticket costs 1,500 lira (50p); day ticket, 4,000 lira (£1.32); monthly season, 35,000 lira (£11.57). Tickets are available from tobacconists and stations.

Taxis are everywhere, and can be hailed in the street or on ranks. Minimum fare is 6,000 lira (£2).

Don't use unofficial taxis without meters.

Phone a radio cab on 00 39 081 556 4444.

Get out of town

Go to Pompeii . Probably the most important example of an ancient city anywhere in the world: villas, shops, brothels and housing for 20,000, buried when Vesuvius erupted in AD 79, it stayed preserved until excavations began in the eighteenth century. Open 8.30am-7.30pm. Tel: 00 39 081 861 0744.

Alternatively, visit the ruins of Herculaneum, also buried in AD 79, open 9am until one hour before sunset. Tel: 00 39 081 739 0963

Take a boat to the islands. Capri, Ischia and Procida are all served by ferries from the Stazione Marittima.

Don't even think about

• Driving. The traffic is horrendous.

• Applying to see the Secret Room at the National Archaeological Museum, stocked with erotica discovered at Pompeii and Herculaneum. It's pretty tame stuff, and keeping it under lock and key is daft.

• Buying any Capodimonte porcelain, unless you feel that drunken clowns clinging to lampposts are the last word in chic.

• Buying anything at a small boutique called Florio in the Via S Biagio al Librai, where three women assistants will sit in total silence, smoking with practised menace, until you shuffle out, embarrassed at having even had the temerity to enter.

• Walking up the Via San Gregorio Armeno, where every presepi shop sells a sickly, sentimental selection of model cherubs, donkeys, angels and mere mortals to adorn traditional Neapolitan cribs.

What the Tourist Board doesn't say

• The red traffic light is an abstract concept to the average Neapolitan driver. He'll ignore it if he can. Pedestrian crossings are almost totally disregarded. Do as the locals do: take your life in your hands and plunge into the seething traffic. Have faith.

• If you are invited into a Neapolitan's home, don't take a bunch of chrysanthemums. They're reserved for funerals.

• The lira is a funny currency. Make sure you know the difference between a 10,000 lira note (worth £3.30) and a 100,000 lira note (worth £33). It's easy to get confused and then be ripped off in your change.

• On public holidays entrance to the enormous Palazzo Reale drops from 8,000 lira (£2.65) to 2,000 lira (66p).

• Carry a good map. There are very few signposts.

• Be careful when ordering the pasta 'penne'. Ensure to pronounce each n, as in 'pen-nay'. Say 'pene' and your waiter will laugh: it means penis.

Getting there

Go flies Stansted-Naples from £88 return, including taxes. Tel: 0870 6076543.

Alitalia flies Heathrow to Naples via Milan, starting at £135 return. Tel: 08705 448259.

British Airways flies direct from Gatwick, starting at £173 return (0845 7733377).

Naples airport is four miles from the city centre. An airport bus costs 3,000 lira (£1) and runs about every hour to the Piazza Municipio. It takes 20 minutes. A taxi takes about the same time and costs about 40,000 lira (£13). A city bus takes about 30 minutes and costs 1,500 lira (50p).

Find out more

Italian State Tourist Board. 1, Princes Street, London W1R 8AY (tel: 0207 408 1254). Brochure line: 090 65 508 925

Italian Consulate. 38 Eaton Place, London SW1. Tel: 0207 7235 9371.

Tourist information. Piazza Gesu' Nuovo, Naples (tel: 00 39 081 551 2701).

Further reading

Naples and Pompeii, Everyman Guides, £16.99.

The Volcano Lover, by Susan Sontag, Vintage, £6.99.

The Nelson Companion, edited by Colin White, Bramley Books, £9.99.

• Stephen Pritchard travelled to Naples with Go and stayed at the four-star Grand Hotel Oriente, Via Armando Diaz 44. Tel: 0039 081 551 12133