It takes a lot to kill a city. The Romans managed it, when they destroyed Carthage and ploughed its fields with salts to ensure it would never rise again.
Vesuvius managed it, burying Herculaneum and Pompeii under clouds of volcanic ash.
Since then, however, cities have proved harder to destroy.
Berlin survived the Red Army, Hiroshima survived a nuclear explosion, New Orleans survived hurricane Katrina.
Sometimes, however, cities fade away. The buildings might remain standing, daily life might continue, but the city slips from the collective consciousness until it's nothing more than a dot on a map, rarely visited by outsiders.
In Europe, where empires have risen and fallen for thousands of years, there are plenty of these lost cities.
Far from the main tourist routes that link modern metropolises such as London, Paris and Barcelona, their ancient glories get only a fraction of the visitors they deserve.
They are Europe's hidden treasures, well worth the effort it may take to reach them.
GDANSK: POWER AND POLITICS
German novelist Gunter Grass said he set many of his novels in his home town, Danzig, because the city itself was "both lost and destroyed".
The destroyers were the conquering Red Army after World War II; the loss came when the city was given to Poland and renamed Gdansk. It is perhaps Europe's best-known lost city, famous for a chequered history that saw it run at various times by Germans, Poles and as an independent city-state.
What is largely forgotten is the power Danzig wielded in its heyday. By the 15th century, it was an important cultural capital, largely autonomous and with a cosmopolitan population that included Scots and Hungarians as well as Germans and Poles.
For a sense of Gdansk's glory days, walk down its Ulica Dluga (Long Street), once the city's most important thoroughfare. It was known throughout Europe as one of the world's great boulevards - the Fifth Avenue of its day - and the elegant merchants' houses still dazzle.
Whether you enter through the Green Gate down by the river, or the Golden Gate to the west, it's hard not to be awed by buildings decorated as opulently as Faberge eggs. Facades of purple and crimson, green and ochre disappear under the details: from chiselled leaves and vines to frolicking Greek gods and stern Roman emperors, as well geometric pop art-style patterns that were centuries ahead of their time.
As stunning as it is, unfortunately it's a total fraud. Like many continental cities, it was rebuilt after World War II. However, the rebuilding of Gdansk was driven by a political agenda: to obliterate the city's German heritage.
Faced with a city centre that was 80 per cent rubble, the Russians were selective in their rebuilding. Only houses from before 1793, the year Danzig was absorbed into Prussia, were reconstructed. Buildings from after 1793 that had somehow managed to survive the first wave of destruction were pulled down.
Staying there The Hotel Krolewski (hotelkrolewski.pl/en), a converted granary on the far side of the river, offers easy access to the old town. Rates start at 280 zloty (about $108).
More info local-life.com/gdansk
RIGA: WARFARE TO WHIMSY
As you walk through Riga's so-called new suburbs - which date to the 19th century - you're under constant surveillance. It's not the hills that are alive here, but the houses. This stretch of the city is home to the largest collection of art nouveau architecture in Europe, a wonderland of buildings adorned with naiads, dryads and giant faces variously happy, sad and fierce.
Some of the most spectacular include the work of architect Mikhail Eisenstein, whose son Sergei went on to achieve international renown as a film director.
As well as bearing testimony to the locals' sense of fun, the houses show that while Riga was founded on a collision between cash and Christianity, cash won out in the end.
The German merchants who established a trading outpost there in 1158 were quickly followed by Albert, Bishop of Livonia, who landed in 1201, on a mission to convert the local tribes.
Like the Spanish centuries later, he relied on warriors to help spread the gospel, bringing with him 23 ships carrying more than 1500 crusaders.
The wars that followed were bitter and barbaric, a reminder that before the Europeans conquered the New World with blood and fire, they practised on each other. In the long run, however, the locals were converted, and got on with the serious business of making money.
The new city of Riga became part of the Hanseatic League, a German trading network that was one of the earliest and most powerful multinationals, fighting successful wars against countries such as Denmark. The Hanseatic cities, which included Danzig, were global power centres and Riga was no exception.
The 800-year-old cathedral may dominate Riga's city centre, but it's the ornate secular buildings around it that illustrate Riga's one-time wealth.
The colourful houses, built in the typical Hanseatic style, have picturesque names such as the House of Blackheads (a 14th-century merchant guild house), and the House of Cats - a building that also demonstrates the local sense of humour. The feline sculptures on the roof tauntingly flash their bottoms at another nearby guild house, which had refused membership to the house's owner.
Getting there Finnair flies to Riga from Helsinki (finnair.com).
Staying there Hotel Bergs is a chic boutique hotel with an atmospheric, old-town setting. Studio suites start at €174 ($285.75), see hotelbergs.lv.
More info liveriga.com
BRASOV: THE WILD FRONTIER
You could call Transylvania Europe's last frontier. Wolves still lurk in the dark forests, but they're a minor danger compared with the more fearsome threats that once stalked these lands.
Fierce nomadic tribes, such as the Cumans and the dreaded Mongols, repeatedly wrought havoc until, in the 13th century, the king of Hungary brought in German settlers to defend the area. The most important task - defence of the Carpathian passes - fell to the Teutonic Knights.
Like their counterparts, the Knights Templar, the Teutonic Knights made their reputation fighting in the Holy Land, but proved just as adept at bloodletting closer to home, also doing tours of duty at Danzig and Riga. They established a series of seven towns built around fortified churches that provided sanctuary in case of attack.
The most magnificent was called Kronstadt (Crown City), although it's known today by its Romanian name of Brasov.
Even today, Brasov is a long way from anywhere. We journeyed a day to reach it, travelling through the bleak landscapes of southern Romania - roads pitted with potholes the size of small lakes, and lined with fetid mounds of stinking rubbish; wild dogs roaming in packs; people scraping a living trying to sell individual rolls of toilet paper to motorists - before rising into the thickly forested mountains.
Nothing in our journey prepared us for the sight of Brasov, an elegant European city in what felt like the middle of nowhere.
The cobblestone streets were lined with well-groomed townhouses immaculately painted in pastel shades; the welcoming central square was lined with bustling outdoor eateries.
Just as it was eight centuries ago, Brasov remains an outpost in the wilderness, offering weary travellers the delights of civilisation; only these days, they include satellite TV and sushi.
Staying there In a 15th-century building, the intimate Hotel Casa Rozelor (casarozelor.ro) has four comfortable suites and one studio. Rates start at €84 ($137.95).
More info simplybrasov.com
NUREMBERG: ANCIENT EMPIRES
Some cities fall off the tourist routes because their history is forgotten. For others, their history keeps people away.
Say "Nuremberg" and chances are the word that comes to mind is either "rallies" or "trials".
This is the city where Adolf Hitler held his massive choreographed tributes to Nazism, and where - as a direct result - the Allies chose to try the surviving Nazi leadership after the war.
However, the Nazi chapter is just one short episode in Nuremberg's rich past. Hitler was drawn to Nuremberg as a venue because of its history as the de facto capital of the Holy Roman Empire. Unlike some imperial capitals, however, Nuremberg was also a wealthy mercantile city, at the centre of four intercontinental trade routes. Martin Luther called it "a sun among the moon and stars"; novelist Ernst Junger described it as "magical, like Venice or Prague".
Nuremberg still has many relics of its glory days, including the daunting Kaiserburg Castle, the seat of the Holy Roman emperors; the Schoener Brunnen (Beautiful Fountain), a 14th-century Gothic fantasy with 40 stone figures cascading down a nine-metre pyramid; and several impressively endowed churches.
What makes Nuremberg really special, however, is its beautiful mediaeval and early Renaissance centre. Although the city was devastated by Allied bombing in the Second World War, the locals painstakingly recreated their maze-like streetscape.
Within a protective ring of moats and city walls - all five kilometres of them - lies a jumble of narrow streets and lanes, gabled roofs, towers and spires and picturesque bridges, including Hangman's Bridge, which separated the rest of the town from the unclean presence of the executioner.
Getting there Nuremberg is an easy train trip from Frankfurt (about two hours) or Munich (about 90 minutes.)
Staying there The Derag Livinghotel Maximilian has comfortable rooms in a central location. deraghotels.de. Rooms start at 45 euros ($73.90).
More info germany.travel
KALININGRAD: THE GHOST SHIP
Not every story has a happy ending. If ever a city could be said to be marooned it's Kaliningrad, a tiny outpost of Russia on the Baltic Sea, separated from the mother ship by 300 kilometres. That's perhaps not so surprising, given Kaliningrad has been Russian for fewer than seven decades.
Kaliningrad has also been marooned by history.
For centuries this city was Konigsberg, the Prussian imperial capital, a cultural and intellectual powerhouse so stimulating that its most famous son, philosopher Immanuel Kant, never felt the need to go anywhere else.
Konigsberg disappeared from the map in 1946 when the conquering Russians - exultant at having finally captured a warm-water port - renamed it Kaliningrad. At the same time, the city went off the radar in another way. As one of Russia's most important military bases, it was closed to outsiders. When the USSR collapsed, the military also declined, devastating the local economy.
The city was finally open to foreigners, but there wasn't much left to see. I found Kaliningrad to be verging on Third-World status: streets rutted, kerbs crumbling, shops devoid of customers. Newspapers reported an AIDS epidemic and warfare between criminal gangs.
Poor Kaliningrad can't even enjoy the cold comfort of its mighty past. Unlike other city centres devastated by war, no organised restoration program was undertaken. The grandiose cathedral was belatedly rebuilt in the 1990s, but Konigsberg Castle, where emperors were once crowned, was demolished after the war.
Where it once stood, the Russians built the 22-storey House of the Soviets, a concrete monument to the Russian empire that has already started crumbling and now sits, derelict, in the shell of a city.
Getting there Air Baltic (airbaltic.com) flies to Kaliningrad from Riga. The easiest access to Kaliningrad is from Gdansk, a bus trip of about three hours.
Staying there Kaliningrad is short on quality accommodation; the Radisson Hotel (radisson.ru/en/hotel-kaliningrad) is an exception. Rates start at 3920 rubles ($147.80).
More info inkaliningrad.com
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- Sydney Morning Herald