Which civilization did the Spanish conquer that was known for their vast empire in South America?

The Incas are recognized for creating one of the largest empires in pre-Columbian America, primarily located in what is modern-day Peru and extending into parts of Ecuador, Bolivia, and Chile. This civilization was remarkable for its advanced agricultural techniques, sophisticated road systems, and remarkable architectural achievements, including Machu Picchu. The Spanish, led by Francisco Pizarro in the 16th century, successfully conquered the Inca Empire, exploiting political instability and using superior weaponry and strategies. The rapid fall of the Incas can be attributed to both military conquests and the spread of diseases brought by the Spanish, which devastated the indigenous population. This historical context underlines the significant impact of the Spanish conquest on the Inca civilization and broader South American history.