Rome's superlative collection of antiquities is displayed in four great venues.
Rome's share of the national collection of antiquities is – understandably – remarkably rich, so much so that the immense horde is now displayed over four venues spread around town, and together known as the Museo Nazionale Romano (MNR). A €7 ticket (€3.50 for reductions) allows access to each of the sites over a four-day period: that's a whole lot of Ancient Rome, but well worth it for something so unique.
Palazzo Massimo alle Terme is the largest single element of the collection, and contains a host of portrait busts, a fascinating display about ancient trade and economics in the basement and, on the second floor, the highlight (for me) of the place: whole frescoed rooms from Roman villas have been reconstructed here, the most jaw-droppingly beautiful of which is the dining room from Livia's villa north of Rome in which birds of all descriptions bob among luxuriant vegetation.
Until its 2000 reorganisation, the MNR was concentrated in the Terme di Diocleziano (Viale Enrico de Nicola 79), the Emperor Diocletian's immense 3rd-century AD baths, the ruins of which were incorporated into a church (Santa Maria degli Angeli) and convent in the 1530s by Michelangelo. What's left here is of mainly specialist interest: stone engravings and funerary urns.
The bulk of the MNR's 'artistic' statuary is on display in the Palazzo Altemps (Via di Sant'Apollinare 46), just north of Piazza Navona. There's a striking 'Gaul's Suicide', an imposing 'Athena with Serpent', the lovely, delicate 'Ludovisi Throne', and many more exquisite items displayed in a beautiful Renaissance palazzo.
Unquestionably the most child-friendly part of the collection is the Crypta Balbi (Via delle Botteghe Oscure 31), located inside the lobby of an ancient theatre, in which Rome's ever-changing cityscape is examined, with displays showing how accumulated debris has raised ground levels and how the locals weren't averse to some blatant thieving from ancient sites to obtain free building materials for their own homes. There are interactive computer displays, plus the chance to join a (free) guided tour down into the basement of the theatre.