At one of the major cities, Lothal, docks were constructed that
could
adjust with the tides

It is believed that tidal motions and their impacts on brick-built structures were studied by Lothal engineers because the walls are made of kiln-burnt bricks.

Explanation:

Lothal is believed to be the first dock in the history of the world. A site belonged to Harappan civilization, today can be found near the village of Saragwala, in the Ahmedabad district.  The town seems to be well ahead of trade and skills of ceramics. The beads and gems were the main goods of import for the western civilization of that time. Modern oceanographers have indicated that the Harappans need to have a deep understanding of tides to construct such a dock on the ever-changing course of the Sabarmati, as well as outstanding hydrography and marine engineering.

because its important to learn about other countries and how high tech they are compared to us. also its good to learn about other cultures and how ours differs and in common also we need to learn about companies that we still buy since they ship it here.

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