Approaching Machu Picchu on foot along Peru's 32-km Inca Trail might sound the stuff of legend. Or, better still, the stuff of Tin Tin. In all honesty, however, it can be more trial than trail.

This ancient Inca road has the irritating habit of scaling one 3,700-meter pass, only to then plunge down into a deep valley and confront one with another 3,700-meter pass. Then after having gone all the way down again, what does one find?

Oh joy!