What is the oldest archaelogical structure/site in the world?

Question

What is the oldest archaelogical structure/site in the world?

Answer 1

Eridu, the first settlement established on earth, is the oldest archeological site in the world.  

Answer 2

Ggantija Temples in Xaghra, Gozo off the island of Malta in the Mediterranean.  Its 6000 years old

Answer 3

pyramids of Giza  

Answer 4

While not impressive buildings the oldest archaeological site, in the strictest sense of the word, are small stone tool working and butchering sites which are 2.5-2.7 million years old and were made by either Australopithecus or maybe an early hominin, perhaps H. habilis. The sites are named Gona and Bouri in Ethiopia, and (a little later) Lokalalei in Kenya.

Terra Amata in France contains the remains of dwellings and is estimated at about 350,0000 years old.