2Machu Picchu, Peru (Inca Empire)

EPerched high in the Andes Mountains, Machu Picchu stands as a testament to the engineering marvels of the Inca civilization.  

Abandoned and hidden from the Spanish conquistadors, this citadel lay undiscovered until the early 20th century. Its precisely cut stone walls and celestial alignments continue to fascinate, offering insights into Incan culture and religious practices.