That's the biggy!
From http://www.s8int.com/sophis5.html :

Archaeologists say the 6,000-year-old structure suggests Neolithic people were engineers as skilled and intelligent as modern man.

The house was found during an examination of Auchenlaich, the longest Stone Age burial cairn in Britain, near Callander in Perthshire. Its walls were made from massive timber posts, and split into separate compartments by light wooden partitions.

Dr. Gordon Barclay, of Stirling University, said: "There is nothing like it anywhere else in Europe. It is an enormous, very sophisticated piece of engineering, built to last." Because there were no metal nails, the house was made almost entirely from timber shaped to fit together with timber pegs, reports the Daily Telegraph.

Dr Barclay said: "They had cattle, pigs and sheep as well as cereals such as wheat and barley. Their tools, such as fine polished axes, were made from stone which they would have quarried nearby."