In the 15th century, when the great powers of Europe chartered the known world, the land that is now known as Peru and the vast landmass of South America were not yet recognized. They were marked as "terra incognita," meaning unknown land, on maps of the time. Despite this, in the peaks and valleys of the Andes Mountains, a people were rising to power. They worshipped a creator god along with the sun, moon, and stars. Within just a century, they managed to conquer and rule an empire that was comparable in size to that of ancient Rome. The dramatic rise and fall of their culture would forever change the course of American and European history. They were known by the name of their all-powerful divine king, the "Son of the Sun," or the Inca.

The city of Cusco, as per legend, was marked as the center of power when the Inca Pachacuti plunged a golden rod into the earth. This place, over 3000 meters above sea level, is not only the highest capital but also the oldest continuously inhabited city in South America. The Inca planned Cusco in a grid pattern, diverting two rivers into channels to refresh the city and irrigate the terraced hillsides. Their genius in stone masonry is evident to this day in the enormous stones that form the foundation of Cusco. The architecture and artistry of the Inca masons are still marveled at in the streets of ancient Cusco.

Colonial buildings like the Convento rest on the shoulders of Inca walls. These great stones held firm even when an earthquake toppled the superstructures in 1956. The Korikancha, or the Corral of Gold, was the empire's most important temple, forming the base of the colonial church of Santo Domingo. It was dedicated to Viracocha, the creator god, and Inti, the sun god. The Korikancha also served as a prison for the gods of Inca enemies, with their icons held both in homage and as hostages. It was a treasure house filled with over 700 sheets of pure gold covering its carved granite walls, life-size gold sculptures of animals, and a massive golden image of the sun adorned with emeralds.

The Inca empire, in honor of the gods who created the first Inca people from maize, was designed in the shape of a great stone puma, a sacred animal to the Inca. The zigzag walls of the 15th-century Sacsayhuamán fortress represent the teeth of this puma, symbolizing the defiance of the Inca stronghold.

With Cusco as their consolidated capital, the Inca were ready for empire expansion. In 1438, Pachacuti and his armies began their conquest along the four roads radiating out from Cusco to the four quarters of the world. Napoleon famously said that an army marches on its stomach, and this was true for the Inca as well. Stations dotted the roads at regular intervals, supplying the warriors. Chaski runners relayed messages across distances of up to 240 kilometers a day, and herds of llamas, which were both edible and agile, carried provisions. As the empire expanded, tribute and treasure flowed back to Cusco, creating enormous wealth. The Inca fashioned gold, the sweat of the sun, and silver, the tears of the moon, into sacred art and built cities, roads, and bridges in the most precipitous places on earth. Sons of conquered chieftains were brought to Cusco to learn Inca ways, ensuring loyalty.

The massive infrastructure of the Inca empire was built through a labor tax, similar to the Egyptians' practice. Over 12 million people extended and maintained more than 10,000 miles of road, farmed the land, and fought enemies. In return, the state provided them with food, chicha beer, and even old age pensions and disability benefits. The Incas, like the Romans, conquered and assimilated, relocating those who resisted and rewarding those who were loyal.

Pisac, the city of towers, was one of the stone cities guarding strategic parts of the empire. Built in the shape of a partridge, as 'pisac' means partridge, it was ruled by an official who ensured a portion of all produce went to the Inca. The air of its market square is still flavored with fresh onions, small corn, fruits, and potatoes, reminiscent of the era of Pachacuti. The nearby amphitheater at Moray served as more than just an agricultural laboratory; it symbolized the generosity of the gods and the relationship between the Inca and their deities.

The entire empire was tallied and taxed using the quipu, a system of colored strings knotted at specific intervals according to the decimal system. Without a written language, the Incas managed their vast empire with these strings. However, the burdensome lifestyle of the royals and the taxes imposed on the populace led to tensions. When the reigning Inca Huayna Capac died, the empire was torn apart by a bloody civil war. Rumors of bearded invaders spread, and chaskis ran to Cusco with news of a floating house at sea filled with bearded men. At this critical juncture, the Spaniards, a mere 200 conquistadors and a handful of priests, arrived.

Archimedes once said, "Give me a lever and a firm place to stand, and I will shift the world." For the conquistadors, the key to shifting the balance of power was the Inca Atahualpa. Francisco Pizarro, using a daring plan, aimed to shift the course of history. In the Andean foothills, 2,700 meters above sea level, lies Cajamarca, a sacred city of the dead for the pre-Incan Kakamaka people. In 1532, this city witnessed the collision between Europe and South America. Atahualpa came to meet Pizarro in peace, but the plaza de armas suddenly erupted with armed horsemen and muskets. In the ensuing chaos, Atahualpa was captured, and the Inca empire began to crumble.

Confined in El Cuarto de la Rescate, Atahualpa offered a room filled with gold and two others with silver as ransom. In today's terms, this would amount to over 250 million dollars. Despite fulfilling his promise, Pizarro had Atahualpa strangled. The treasures of the Inca, once symbols of their magnificent culture, were melted into ingots and shipped to Spain. Some of this wealth was used to glorify the Christian god of the conquerors, as seen in the baroque Cathedral in the Plaza de Armas.

When Pizarro took Cusco, the Inca turned to the mountains, their last refuge. Ollantaytambo, in the Sacred Valley, is a testament to the Inca's engineering genius, with its terraced fields and the Temple of the Sun. However, it was unfinished, a sign that its builders were interrupted by the advancing Spaniards. It fell to just 50 horsemen.

The question then arises: where did the Inca go? A mysterious motif in Ollantaytambo points towards the heavens, suggesting a place of offerings and deliverance. This leads us to the lost city of Machu Picchu,

hidden in the dense cloud forests of the Andes. Guarded by a deep gorge and accessible only through steep terrain, Machu Picchu was a marvel of Inca architecture and engineering. Hiram Bingham, who rediscovered it in 1911, described it as an unbelievable dream. Built by Pachacuti as a country palace, it featured quarried stones, a natural mountain spring, and more than 200 buildings. The city was divided between the commoners and the elite, and it also served as a religious center. The Intihuatana, a granite monolith, was used for astronomical purposes, predicting solstices and controlling the seasons. Machu Picchu was used for only about 50 years before being deserted and reclaimed by the jungle.

The fall of the Inca empire also meant the disappearance of their gods – Viracocha, Inti, and others associated with the heavens, rocks, springs, valleys, and high places. They are now remembered only in art and architecture, as the lost gods of a once-great civilization.