The Fertile Crescent. Invention of the writing system predominant in most of the world today, domestication of plants (esp. wheat) and animals, and the idea of the settled life as opposed to nomadic existence, and possibly astrology.
The Nile Valley. Invention of Hieroglyphic writing, irrigation systems, astronomy and the calendar, monumental architecture. This civilization remained vital until at least the arrival of Rome.
The Indus Valley. Civilization took place very early on the sub-continent, and at some point it may be proven to have started around the same time as the Fertile Crescent and the Nile Valley civilizations. Hinduism probably dates from the very earliest period, and remains a dominating force in India. This civilization is the birth place of many religions.
China. Chinese civilization may be slightly younger than the other three listed here, but its origins are still very, very ancient. The Chinese also invented their own version of writing that continues to the present. The Chinese language is quite different from those of other major civilizations, being based on monosyllabic tones. Very early bronze and other metal work are in many ways so sophisticated that they would be difficult to reproduce today.
The contributions I've mentioned for each of these four date from their very early periods. All four continued to make important contributions to the sum total of human knowledge and understanding. All had significant impact on how the regions in which they dominated evolved culturally. The impact of all four can be seen today, often in places far removed from their points of origin.
You only asked for the first four, but perhaps you should consider others as well. Putting the New World and lost African civilizations into their proper places in a time-line is a bit more complicated and less certain. The Spanish destroyed most of the written records of the New World that they found, so both the civilizations of the New World are still being unraveled. Corn, chili, and chocolate, the Three C's, are essential to the modern diet, as are potatoes (no Potato Famine without spuds). Astronomy and calendar making were important to these New World civilizations, and almost certainly originated independently of China and the other early civilizations. The wheel was known, but only on children's toys. The Inca form of writting was a complicated system of knotted cords hung from a stick ... probably pretty limited compared to other forms of record keeping.
Even more problematic are the Lost African civilizations where, so far as we know, writing never developed. When and where civilizations rose and fell into oblivion in sub-Saharan Africa may not be fully appreciated for another hundred years.
Rome evolved out of Grecian civilization, which in turn sprang from earlier Mediterranean civilizations all of which are lineally related to the Nile River and the Fertile Crescent civilizations. Of course, all of this is far too simplistic a charting than the historical realities. Trade between regions probably began long before the invention of literacy, and hence history (written records of the past). Ideas, products and technologies were exchanged and modified so often and frequently that actual points of origin in time and place are mostly lost to us. An example is the development of metallurgy that appears very early in all four of the earliest civilizations. Who invented metallurgy, a technology almost as important as writing? Humans invented it, recognized its value and developed it into materials that make possible space flight, throw-away computers, and nuclear energy in the Current Era. We stand on the shoulders of giants, most of whom will forever remain anonymous.