At same link, www.cracked.com/article_20206_5-shockingly-advanced-ancient-buildings-th… …the Marib Dam in the Yemen, is featured with some nice images of how it is now. This must have been a really impressive structure and its downfall is described in David Keys book, Catastrophe: an investigation into the origins of the modern world (Century, 1999). It was over a thousand years of age when it was breached, constructed in around 750BC. This takes it back to the floruit of the ancient kingdom of Sheba. In the Bible it was associated with frankincense and myrrh and in the ancient world every ancient temple required sweetening with these plants – especially where animal sacrifice took place.
The article describes the complex as possessing canals with gates, sluices and spillways, and it irrigated a vast area of water fed agriculture. As spices were the source of the wealth of Sheba one wonders if this is what it was designed for, to increase the terraces where these plants could be grown. It is also known they established a kingdom in Nubia (modern Sudan) also known as Saba, in order to grow the incense plants (species grew their naturally which appears to be why it was colonised from southern Arabia). The dam was 2000 feet long and converted large tracts of ancient Yemen into a powerhouse where incense plants were part of a trade that flourished during the Assyro-Babylonian era, the Persian and Greek eras, and especially in the Roman period. After Christianity spread through the Roman world incense lost its value and the dam itself collapsed in the 6th century AD.
Pumapunku in Bolivia has been likened to a huge LEGO like construction using hundreds of stone building blocks which were cut and shaped with chisels, an incredible amount of man hours required. Each stone had an identical appearance and slotted together one after the other. The largest stones was 25 feet long and 17 feet wide.
Gobekli Tepe in Turkey has been featured here on several occasions. Situated on a hill overlooking the Syrian Plain it is currently dated as early as 9000BC. The article claims it might even be older than that as they have not yet reached the lowest levels.