Baku, Tbilisi and Yerevan, the three Caucasus capitals

Between the Black Sea and the Caspian, south of the great wall of the Caucasus mountains, lie three small countries: Azerbaijan, Georgia and Armenia. All three were part of the Soviet Union and became independent in 1991. Beyond that, they differ a great deal. Azerbaijan is a mostly Muslim country of Turkic language and culture. Georgia and Armenia are ancient Christian nations, each with its own church and its own alphabet. Their capitals reflect those differences.

There is a complication. Azerbaijan and Armenia fought wars in the 1990s and again more recently over the region of Nagorno-Karabakh, and their border remains closed. A journey through all three goes by way of Georgia, which keeps good relations with both.

Baku

Baku stands on a peninsula on the shore of the Caspian Sea, and it has been shaped by oil. The region has been known for its oil seeps and burning gas since ancient times. In the late nineteenth century it became the scene of one of the world's first oil booms, financed by the Nobel brothers and the Rothschilds, and the oil barons built grand mansions in a medley of European styles. In recent decades, a second oil and gas boom has transformed the city again, with a striking skyline of modern buildings, among them the three curving glass Flame Towers and the swooping white Heydar Aliyev Centre.

At its heart lies the old walled city, Icherisheher, a maze of lanes, mosques, caravanserais and the palace of the Shirvanshahs, guarded by the mysterious Maiden Tower. It is a World Heritage Site. On the Absheron Peninsula around the city, natural gas burns from the ground at a hillside called Yanar Dag. A fire temple, used by Zoroastrian and Hindu worshippers, stands at Ateshgah.

Tbilisi

Tbilisi, the capital of Georgia, lies in a gorge of the Mtkvari river, and it is one of the most charming capitals in this part of the world. According to legend, it was founded in the fifth century by a Georgian king who discovered its hot springs, and its name comes from the Georgian word for warm. Its old town is a jumble of churches, mosques, synagogues and houses with carved wooden balconies, climbing the hill below the ruined Narikala fortress. In the Abanotubani district, domed sulphur baths, fed by the hot springs, are still in use. Georgian food and wine, from the vineyards of Kakheti to the east, are a constant pleasure.

Yerevan

Yerevan, the capital of Armenia, is one of the oldest continuously inhabited cities in the world. An inscription records the founding of the fortress of Erebuni on its edge in 782 BC. Much of the modern city was built in the Soviet period of pinkish volcanic tuff, which glows in the evening light, giving it the name of the pink city. On a clear day, the great snow-capped cone of Mount Ararat, across the border in Turkey, dominates the view. The Matenadaran holds one of the greatest collections of ancient manuscripts in the world.

Beyond Baku, Sheki lies in the foothills of the Caucasus in the north-west of Azerbaijan, a town of orchards and old stone houses that grew rich on silk. Its Khan's Palace, from the eighteenth century, is a small summer palace with painted walls and windows of shebeke, a latticework of wooden pieces fitted together without glue or nails and filled with coloured glass. A great caravanserai, built for the merchants who once came through the town, still stands nearby.

Explore Worldwide's The Best of Azerbaijan, Georgia and Armenia, eighteen nights, combines all three. In Azerbaijan its places include Baku and the Absheron Peninsula, the old silk town of Sheki with its khans' palace, Shamakhi, the copper-working village of Lahij and the old church at Kish. In Georgia they include the Kakheti region, with Alaverdi, Gremi, Telavi, Vardisubani and Kondoli.

Explore Worldwide's The Best of Georgia and Armenia, fifteen nights, focuses on the two Christian countries, with Yerevan, Echmiadzin, Garni, Geghard, Khor Virap, Noravank and the Noratus khachkars.

Spring and autumn are the best seasons in all three countries. Summer is hot in the lowlands, especially in Baku and Yerevan, and winter brings snow to the mountains.