Final answer:
The Pyramids at Giza were the first world monument built, around 2500 BCE.
Step-by-step explanation:
The Pyramids at Giza were built around 2500 BCE, making them the world monument that was built first. The Parthenon was built around 450 BCE, the Colosseum was built around 70 CE, Chichen Itza was built around 600 CE, and Angkor Wat was built around 800 CE.
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