Several wooden wells from Germany have been precisely dated by archaeologists, yielding not only very revealing information from the first farmers of that area (and by extension of all Europe) and their construction techniques but also most valuable paleoclimatic information from the reconstructed and precisely dated tree rings.
|Figure 1. Wooden well constructions and Neolithization.|
LBK wells from (A) Eythra 1, (B) Eythra 2, (C) Brodau 1, and (D) Altscherbitz. (E) Central European loess distribution  with the superimposed phases of expansion of the LBK (lines), based on 14C dates , and the maximum extension of the LBK (light blue) along with the 12 known early Neolithic wells featuring waterlogged wood preservation.
Willy Tegel et al. Early Neolithic Water Wells Reveal the World's Oldest Wood Architecture. PLoS ONE 2012. Open access → LINK [doi:10.1371/journal.pone.0051374]
The European Neolithization ~6000−4000 BC represents a pivotal change in human history when farming spread and the mobile style of life of the hunter-foragers was superseded by the agrarian culture. Permanent settlement structures and agricultural production systems required fundamental innovations in technology, subsistence, and resource utilization. Motivation, course, and timing of this transformation, however, remain debatable. Here we present annually resolved and absolutely dated dendroarchaeological information from four wooden water wells of the early Neolithic period that were excavated in Eastern Germany. A total of 151 oak timbers preserved in a waterlogged environment were dated between 5469 and 5098 BC and reveal unexpectedly refined carpentry skills. The recently discovered water wells enable for the first time a detailed insight into the earliest wood architecture and display the technological capabilities of humans ~7000 years ago. The timbered well constructions made of old oak trees feature an unopened tree-ring archive from which annually resolved and absolutely dated environmental data can be culled. Our results question the principle of continuous evolutionary development in prehistoric technology, and contradict the common belief that metal was necessary for complex timber constructions. Early Neolithic craftsmanship now suggests that the first farmers were also the first carpenters.
I would not dare to claim as much as they say in the last sentence because we do know of Epipaleolithic carpentry in form of boats and rows as well, and let's not forget what we know of the Neanderthal carpentry including wooden walls and utensils. But it is later revealed in the conclusions that their intention is more to compare with the Metal Ages than with the Paleolithic:
This study demonstrates that the first farmers were also the first carpenters, contradicting the common belief that the invention of metal woodworking tools more than a thousand years later was imperative for complex timber constructions. Settlers of the early Neolithic time were able to build sophisticated corner joints and log constructions, which fulfilled all of the static requirements of massive water well linings. Their technical skills further imply the existence of complex constructions for LBK longhouse architecture .
But the wells and their techniques are anyhow interesting, very especially because we do not get to see such well preserved ancient pieces of wood but seldom. Both cogged and mortise-and-tenon unions were used in the construction of the wells.
Figure 5. Basal frame construction of well A.
(A) Wedged tusk tenon joint. (B) 3D laser rendering of the basal frame.
Well A (Eythra, Saxony) not only displays these innovative mortise-and-tenon (wedged variant) joints but the comparison of the age of its timbers with others used in the surrounding area, indicate a settlement of at least one century, suggesting that the villages of the Danubian Neolithic were anything but provisional.