Mist opportunities at Machu Picchu

The disappointment is enough to make me feel ill. I have spent two days getting here, having negotiated rough mountain roads by motorcycle, and spent a considerable amount of money on this once-in-a-lifetime experience: seeing Machu Picchu. But just as I arrived, a thick fog enveloped the mountain range. I can barely see the slippery stone steps I'm climbing, never mind the ruined city spread out below me.

I stand in a huddle of tourists who rushed to catch the first bus, at 5.30am, to the historic site. We all mutter variations on a theme: "Such a shame"; "Well, we can still explore the city, I guess"; "I can't believe it, after I've come all this … wait. There it is!"

As the sun rises, the fog clears, and Machu Picchu, the mysterious "lost city of the Incas", slowly reveals itself. Built at 2,430 metres above sea level in the middle of a tropical mountain forest, it sits snugly in a saddle on the eastern flank of the Peruvian Andes. The granite walls and terraces of the city are flooded by sunlight in what is an awesome display. There is no muttering now, making the click of camera shutters seem all that much louder.

Standing on the edge of the city is a dizzying experience, with the mountains dropping away to deep and narrow valleys that have been cultivated continuously for well over 1,000 years. From atop the city walls can be seen a meander in the Rio Urubamba, where construction workers are building a hydroelectric dam.

No one is quite sure why Machu Picchu exists. It was built sometime in the mid- to late-1400s, an urban architectural exclamation mark of the Inca empire at its height. Perhaps it was ceremonial, perhaps it was a summer retreat for rulers, or maybe the Inca planned it as a last stronghold.

The city appears to be divided into quarters: one for farmers, near the massive cultivated terraces and hanging gardens; one for industry; one for royals; and one with temples, for the religious side of life.