Roman Painted House (Dover, Kent): Called Britain's "buried Pompeii," this 1,800-year-old Roman structure has exceptionally well-preserved walls and even an under-floor heating system used by the Romans. It's best known for its unique bacchic murals.

Avebury (west of Marlborough, Wiltshire; east of Bath, Avon): Although not as famous as Stonehenge, this is one of Europe's leading prehistoric monuments. Its circle of more than 100 stones -- some of them weighing in at 50 tons -- is arrayed on a 28-acre site.

Roman Baths (Bath, Avon): Dedicated to the goddess Sulis Minerva, these baths were founded by the Romans in A.D. 75. Among the finest Roman remains in the country, they're still fed by Britain's most famous hot-water spring. The site of the Temple of Sulis Minerva is excavated and open for viewing.

Corinium Museum (Cirencester, in the Cotswolds): This regional museum contains one of the best collections of archaeological remains from the Roman occupation of Britain. You'll see Roman mosaics that have remained in Britain, along with provincial sculpture, such as figures of Minerva and Mercury.

Hadrian's Wall (near Hexham, Northumberland): A World Heritage Site, this wall -- now in ruins -- was ordered built by Hadrian, the Roman emperor, in A.D. 122 to hold back barbarian invasions from the north. Marking the far northern border of the Roman Empire, the wall stretched 118km (73 miles) from Wallsend, or Wall's End, north of Newcastle upon Tyne in the east to Bowness-on-Solway beyond Carlisle in the west. A milecastle (small fort) was added at every mile along the wall. Garrison forts, some quite large, were built behind the wall. A highlight is Vindolanda, the last of eight successive Roman forts built on a site adjacent to the wall.