The Sun and the Moon pyramids, constructed from millions of earthen bricks, are the largest pre-Columbian structures in South America. Large-scale human sacrifice at Huaca de la Luna became evident when archaeologists uncovered the remains of at least 34 sacrificed adult male individuals in the soft clay of the southeastern court, at the foot of the mountain. They had been bound, and judging by the type of wounds that had been inflicted, had probably been captured in battle. The sacrifice represents a single ritual event linked by archaeologist Steve Bourget to a season of torrential rains caused by an extreme case of the maritime El NiƱo phenomenon, which may have caused the final abandonment of this site. The larger, but less well preserved Temple of the Sun was once home to a wealth of gold artifacts, but these were looted by colonists during the 17th century.