When one considers ancient civilizations most think of the Egyptians, Greeks, Romans, Carthagians .. those based around the Mediterranean. Far across the ocean from those who held sway in Europe though a number of Ancient Civilizations not only flourished but thrived well past the date when the Roma Empire (as an example) had collapsed.
As one journeys South in the Americas from Mexico, throuhg Guatemala and onwards into Ecuador and Peru you can discover thetraces and remains of some of the worlds grandest civilizations – that of the Olmecs, the Aztecs, The Mayans and the Incas.
While it is (as you would assume) my recommendation to visit a lot of South America and Central America as individual countries on small manageable trips rather than just one long trip as many seem to want to do, if you are after a trip to take in Ancient Civilizations then this is a possibility to do within three weeks (inclusive of flights) and cover the Olmecs, Aztecs, Mayans and Incas.
A three week trip would cover the basics .. one that wanted to cover the four civilizations in depth would take considerably longer, but the shorter one is suitable for most working people on holiday or those seeking an introduction to South and Central America.
For a tour that fits within a three week period we would suggest something along the lines of the following ..