Even if you aren’t planning to spend time around Lake Titicaca, the rail journey south to Puno is worth taking. The journey starts in the Cusco region and takes around twelve hours, covering a soul-stirring route that climbs slowly through stunning green river valleys to a desolate landscape to the pass, beyond the town of Sicuani. From here it rolls down onto the altiplano, a flat high plain studded wih adobe houses and large herds of llama and alpaca, before reaching Lake Titicaca and the port city of Puno.
If Lima is your destination, consider the 20-hour direct highland route northwest from Cusco through Abancay and then down to the coast at Nasca. Known as the Nasca-Cusco Corridor, it offers access to a range of potential stop-overs on the way: the archeological sites of Choquequirao and Sahuite; the city of Abancay and protected mountain forest area of Ampay; the thermal baths at Chaullanca and the alpaca and vicuña centre at Puquio; and, of course, the mysterious archeological sites around Nasca itself.