Great Advice.
Always keep in mind that international airfares are considerably higher than domestic fares. There are luxurious bus services all along the route, though some are extremely long, for example Santiago to San Pedro de Atacama is around 24 hours, so a plane ticket here may be indicated.
Here is a site that shows the quality of long-distance buses:
http://www.pullman.cl/nuestra_flota.htmlBus companies in Chile
http://www.gochile.cl/info/xporte/bus.aspThe route suggested by Eileen is the best:
San Pedro de Atacama (skipping Antofagasta), Iquique, Arica, Arequipa, from Arequipa take the direct bus to Cusco. In Cusco take the trip to Machu Picchu, but stay at least one night at Aguas Calientes. Return across the Altiplano to Lake Titicaca and Puno (skipping Juliaca), then La Paz, Oruro, Jujuy, Salta, Cordoba and Mendoza. Then a brief hop over the Andes back to Santiago.
Take the overnight buses if possible in Chile, but you may prefer day buses in Peru and Bolivia for the scenery.
To get inside Travelpod traveller information on each city you plan to visit, access the Travelpod site, and where it says “search” on the right, type in the city or town, and there you have all the comments, good and bad, from your fellow travellers. For example:
http://www.travelpod.com/s/san+pedro+de+atacamaHope this helps
Cheers
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