Francisco Pizarro had toppled the Inca Empire, captured its Emperor Atahualpa and demanded a room of gold and two rooms with silver, he got the treasure but still executed Atahualpa. Hearing of this Rumiñahui took his forces towards the Northern Inca Capital of Quito, where it's believed he buried the gold then he heard that the Spanish forces were marching towards Ecuador to capture him. So he decided to burn Quito to the ground to take the glory away from the Spanish of taking the city, then he took the Sun Virgins and killed them to preserve their purity. Then he prepared his army for the battle.
The battle 
Pizarro sent his lieutenant Sebastián de Belalcázar to capture Rumiñahui, take the gold as well as the city of Quito. While in Ecuador, Rumiñahui rallied his forces and marched them south. Both forces met at the valley of Mount Chimborazo. Neither the Spanish or the Incas had the upper hand at the beginning but then Rumiñahui's army started beating the Spanish back even though the Spanish possessed guns and cannons, Belalcázar was about to retreat so he wouldn't have a lot of casualties, but then the volcano erupted so the Incas saw it as an omen from the gods so they started to run away. This battle was the last stand of the Incas before the fall of the Empire. Eventually, Rumiñahui was captured and tortured but he would not reveal where the gold was hidden. He took the knowledge of the treasure's location to his grave. The Spanish never found it.