any museum in which artefacts of that time are preserved?
Yes, there are.
Maya civilization
There are a great many museums across the world with Maya artefacts in their collections. The Foundation for the Advancement of Mesoamerican Studies lists over 250 museums in its Maya Museum database, and the European Association of Mayanists lists just under 50 museums in Europe alone.
who held the power in the maya civilization The king. when did this civilization develop? 2600 BC. which materials and technology are used by the people of that time to build their cities? Neolithic technology; stone, limestone, volcanic tuff, sandstone and fired bricks. which was the common language spoken at that time? Proto-Mayan.
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Maya civilization [SEP] Museum collections
There are a great many museums across the world with Maya artefacts in their collections. The Foundation for the Advancement of Mesoamerican Studies lists over 250 museums in its Maya Museum database, and the European Association of Mayanists lists just under 50 museums in Europe alone.