The Indus River Valley civilizations

The early civilization came from the river valleys, known as the Harappans, this civilization was in the area of modern-day Pakistan in the Indus Valley, dating as far back as 7,000 BCE.

Around 3,300 to 2,000 BCE, the early Indus Civilization appeared, and that's when the Acadians and the Sumerians began interacting, and then around the 3rd millennium was when the empire of Sargon the Great was established.

Then around the mature period, which is around 2600 BCE, is where most of the advanced structures were found, and if we go to Egypt, around 2500 BCE is roughly when the Pyramids were built.

Then around 1600 BCE is considered the late Indus valley civilization, which is where the Babylonian empire was founded

The Punjab region in Pakistan is where most of our archaeological dig sites are about the Indus Valley Civilization, found around Harappa, which is why it is known as the Harappan civilization too, the largest site is Mohenjo-Daro in the Sindh region.
We believe that over 40,000 people was living in that region alone, with around Harappa and Mohenjo-Daro, there are over 1000 sites scattered all around both regions.

The reason why we think that this is a civilization is because of the sheer size of it all, the standardization of measurement and weight, we have found them using aa measurement of 1.6mm which is precise, we can speculate that there was some cultural interchange, sin they were using bricks that were a standard size so measurements were needed.

In Mohenjo-Daro, we found some sites that these people lived in, from citadels, to public baths, and what was impressive is that we found sewerage systems for carrying waste, along with houses with wells.
Their jewelry is intricate and complicated with shells gathered from the Arabian Peninsula, and the type of jewelry was not only found at these sites but also found in Mesopotamia too, and we speculate that there were probably ships transporting cargo from Mesopotamia and the now modern-day Mohenjo-Daro region. 
Materials from what is now modern-day China and India, they also had their own writing system and they also made Symbols along with a wee known symbol of a Nazi Swastikas', before Hitler used in in his campaigns it is a common symbol in Hinduism, often meaning good luck,.
But we don't really know much about them, other than the stuff we found at dig sites, and since we can't decipher their writing.

One of the strangest things about the Indus Valley Civilization is 'why did it end', they seemed to be thriving with good ties and imports from other civilizations, some ideas on why it ended were maybe they were invaded, some other theories are that it was because of climate change .

As one of the earliest civilizations on earth with a speculation of their whole population maybe reaching