Although most of the museums in Rome are free for those under 18 or over 65 and reduced for those from 18-25, they are not so for the majority who are outside those categories. The unfortunate truth is, however, that the quality of the exhibits of any given museum is on the whole reflected in the price of the ticket.

To start with the recently-refurbished Museo Napoleonico. Although the most interesting exhibit, the fine bust of Paolina Bonaparte Borghese by Canova, is not on display at the moment, these attractive rooms offer a most enchanting selection of portraits of members of the Bonaparte family, as well as refined Empire jewellery, furniture and bibelots. This is reasonable value at e2.60. Piazza di Ponte Umberto 1, tel. 0668806286. 09.00-19.00. Mon closed.

The Centrale Montemartini offers the idiosyncratic blend of an eclectic range of classical works from the Capitoline Museums deposits alongside the gloriously low-tech electrical generating equipment of this former power plant, including splendid sets of giant tools, which some may find more interesting than the surrounding statuary. Of great beauty is the huge 6th-century ridge-tile from the Foro Boario, but the prize goes to the ravishing and unforgettable 2nd-century BC statue of the muse Polymnia. This is also reasonable at e4.13. Via Ostiense 106, tel. 0639967800. 09.30-19.00. Mon closed.

Displaying an unrivalled collection is the Museo Nazionale Etrusco di Villa Giulia, a magnificent complex, now handsomely refurbished, with the exhibits definitively arranged. Anyone can appreciate the extraordinary beauty and refinement of the jewellery in gold, amber and semi-precious stones, but perhaps the greatest glories of the collection, which single it out from all others, are the magnificent sculptures in terracotta which once decorated Etruscan temples. Such works were very much an Etruscan speciality, and some are probably by the famous sculptor Vulca, who was commissioned by the Roman king Tarquinius Priscus to make statues for the temple of Jupiter on the Capitoline hill at the beginning of the 6th-century BC. No less beautiful is the celebrated terracotta sarcophagus, bearing the sculpture of the bride and bridegroom. This museum is excellent value at e4. Piazzale Villa Giulia 9, tel. 063226571. 08.30-19.30. Mon closed.

Rather specialised, but with exhibits of the highest order, is the Museo Nazionale Romano Palazzo Massimo alle Terme, with artefacts from sites excavated within Rome and the surrounding countryside. There is superb statuary, including such famous pieces as the Ephebe of Subiaco, the Anzio Girl (Fanciulla di Anzio), two versions in marble of the Discobolus, Roman copies of Myrons bronze original, or the ravishing Sabine Girl of about 135 BC. Unique to this museum are the frescoes and stuccoes from the Villa della Farnesina and the exquisite frescoed rooms from Livias villa at Prima Porta, of which the so-called garden chamber on its own justifies the visit. These are on the top floor of the museum, together with an enormous range of Roman mosaics, outstanding amongst which are the stupendous floors from the Villa dei Septimii on Via Cassia. Unfortunately, visitors are not allowed to wander freely on this floor and must join accompanied groups which are pushed along a little too fast for some tastes, but by holding up the guide with pertinent questions it is possible to extend the allotted time. More expensive at e6, but worth it. Largo di Villa Peretti 1, tel. 0639967700-0648903500. 09.00-19.45. Mon closed.

The Galleria Doria Pamphilj may seem expensive at 8, but it includes an excellent and entertaining audioguide. Considering that the private collection is no burden at all on the public purse, and the superlative quality of a number of the paintings on display, the price may seem more reasonable. Velsquezs Innocent X is without doubt the finest portrait in Rome, and one of the ten finest in the world, while many of the other paintings are of a level rarely seen outside major national collections. The rooms of the palace are also splendid. Piazza del Collegio Romano 2, tel. 066797323. 10.00-17.00. Thurs closed.

There are some museums, well-worth visiting, that are free of charge. First of these is the Hendrik Christian Andersen Museum, with two enormous rooms full of the sculptures in marble and plaster of this not especially talented Norwegian-American artist. The handsome neo-renaissance building, Villa Helene, built by the artist as atelier and display premises for his works, is worth the visit, and anyone with a sense of humour will enjoy the kitschness and mawkishness of most of the works. Via P. S. Mancini 20, tel. 063219089. 09.00-19.00.

Visitors to Palazzo Massimo mentioned above should also visit the Aula Ottagona at the far end of Piazza della Repubblica, to see, if nothing else, the superb bronzes from the 1st and 2nd centuries BC of the heroic Hellenistic Prince and the movingly battered Boxer Seated. Via Romita, tel. 064880530. 09.00-13.00, 15.00-18.00.

The refined and personal collection of mostly 19th-century furniture and furnishings which constitutes the Museo Mario Praz is also free. It is just round the corner from the Museo Napoleonico, and a visit takes only an hour or so. Palazzo Primoli, Via Zanardelli 1, tel. 066861089. 09.00-19.00. Mon closed.

Lastly, mention must be made of what is not technically a museum, but has many of the attributes of one: the church of S. Maria del Popolo. Here there are first-rate paintings by Caravaggio, glorious frescoes by Pinturicchio, 16th-century stained glass, the Chigi chapel designed by Raphael, decorated by various hands and which also includes important sculptures by Bernini. The setting in Piazza del Popolo is superb and offers ample choice for refreshment after such cultural exertions. A visit to this church can be combined with one to the Hendrik Christian Andersen Museum, as they are quite near each other. Piazza del Popolo 12, 063610836. 07.00-12.15, 16.00-19.00.

For the Settimana della Cultura, 24-30 May, admission to state-owned museums is free. For information see www.beniculturali.it.

Picture: The Hendrik Christian Andersen Museum is in a handsome neo-renaissance building in the Flaminio area.