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Prehistoric people transported 2-tonne stone by boat
(www.newscientist.com)
This is a space to discuss ancient archaeology, history, philosophy, etc.
Though a quick search says we've likely had at least makeshift boats for as long as 50 to 60 thousand years so kinda broad span if 3000 bc is the first written history(egyptians, 5k years)
If the monument was built around 5 thousand years ago i guess the timeline suggests there were more advanced boats earlier than we thought, so that's kinda cool