In 1487 for the re-consecration of Great Pyramid of Tenochtitlan the Aztec guys sacrificed thousands of people. According to the historical sources the victims were walking slowly in 4 queues (each several kilometers long) toward the temple and there the priests killed them and cut their heart out continuously for days:
"At the inauguration of this Great Temple in 1487, Ahuizotl ordered the sacrifice of many prisoners of war; an average of 1,000 victims a day were sacrificed over a period of twenty days. Each day blood ran like a river onto the pavement of the Great Plaza, and the stairs of the great pyramid were literally bathed in blood."
We denounce the bloody conquest of Mexico these days, but the Aztecs themselves weren't exactly angels back then.