There were some in Africa that were equal to or more advanced than those in Eurasia — i.e. Nok and others like it. One might mention the Gajiganna Culture. Cultures on that general level were not rare at the time or in times fairly soon after in West Africa, but those were notably the oldest and most advanced (or among such) in their region at the time. There were also some that were less advanced and/or did not become so until much later. Of course these were not the most advanced cultures on earth…
…Tangentially speaking, not to belabor the point too much: there are especially important developments in Africa that are early and especially stand out by by global standards: for instance, the likely invention of iron metallurgy in West Africa the Igbo region ca. 2000 BC, 1,000 years before its only other independent discoveries in two other places — China and the Near East. Another is one of the few and oldest independent inventions of pottery other than that of Asia (both around the Mesolithic in either Southern Mali or Central Sudan and somewhere between N. E. Russia and China).
I was very interested in this subject at one time, and I did a lot of research into when metallurgy appeared in Africa and whether iron smelting was an independent development in Africa as so many insist.
I read ~90 pages out of a book on subject that was available for reading on the Internet. The author was a respected anthropologist. The claim was that metallurgy was independently developed in Africa in Nigeria before anyone else, and that Africans completely skipped the Copper and Bronze Age precursors and went straight to the Iron Age, a mighty feat if true. However, the conclusion that I reached after all that reading is that Africa did not independently develop metallurgy. In fact, metallurgy developed much earlier in Eurasia as the Copper and Bronze Ages, which appeared long before the Iron Age, the last stage of metallurgy.
So metallurgy itself was developed probably centuries if not millennia before its appearance in Africa with the smelting of copper and bronze, two earlier stages that never showed up in Africa until much later.
And the smelting of iron also does not appear to have developed independently in Africa. Instead it developed first in Anatolia. Anatolians were already familiar with the smelting of copper and bronze, and it appears that iron smelting was invented here some time in the 4th Century BCE.
It then slowly filtered over to Libya, a process that took centuries. The Libyans or pre-Carthaginians traded a lot down through the Sahel with Sub-Saharan Africans.
So iron smelting somehow made its way down the Sahel to Nok, Nigeria, where it appeared 2,900 BP or 900 BCE. It is this well-known Nok development of iron smelting that is the evidence used by misguided people (often Afrocentrists) to claim independent development of iron smelting in Sub-Saharan Africa before anyone else on Earth.
Other than the facts, there were some other suspicious things about this theory. First of all, the claim that Africans were so advanced that they skipped the Copper and Bronze Ages altogether and leaped right to the Iron Age seems suspicious. The normal trend in metallurgy was copper -> bronze -> iron. It went like this the world over. Why would Africans be so advanced that they leapfrogged over the rest of the planet and skipped the first two possibly necessary stages.
Also iron smelting did not appear with the Igbo as claimed above but instead was developed by the more North African/Sahel (and later Islamic) influenced Nok Culture in the far north of Nigeria in what is now the Hausa-speaking region part of Muslim Nigeria.
Nevertheless, I like the Nok Culture, and in my opinion it takes a fairly advanced culture to even borrow things from other cultures, and Nok was very advanced for its time 2,900 YBP.
I would also like to point out that most cultural innovations are actually borrowings. Few major cultural developments occurred independently.
The alphabet is a good example, and most of the world’s alphabets borrowed ultimately from the Phoenician alphabet, the first character set that went on to conquer the world. Even Indian scripts are borrowings from the Phoenician, as are the Arabic, Aramaic, and Persian scripts, etc. There is nothing wrong with borrowing a major cultural advance. Most cultures on Earth obtained most of their major cultural advances via borrowing as opposed to independent development.
Furthermore, it is important to note that after iron smelting occurred at Nok, it spread very quickly through Africa. It appeared in Tanzania not long afterwards, and it rapidly spread through much of the region. Furthermore, Africans made wide, almost stunning variety of innovations in iron smelting, and these innovations were indeed independent developments. Speed of cultural transmission and improvements/innovations in major cultural borrowings are also examples of advanced cultures.