The people who lived in Eastern Germany around 7,000 years ago are thought to have been some of the first farmers. Now, new archaeological evidence suggests they were also surprisingly skilled woodworkers, crafting intricate water wells some two thousand years before metal tools were forged in Europe.

Sophisticated in construction, four wells discovered near Leipzig were built using stone carving implements and wooden mauls and wedges, said Willy Tegel, a researcher at the Institute for Forest Growth at the University of Freiburg in Germany.

"The first farmers were also the first carpenters," Tegel and his colleagues wrote in a study published this past week in the journal PLoS One.

The people who built the wells were members of the so-called Linear Pottery Culture, which produced pottery with distinctive incised lines more than 6,500 years ago. Archaeologists believe these ancient people migrated from areas that are now the Ukraine and Slovakia through the fertile regions of Central Europe.

The wells were discovered as part of an ongoing excavation of areas about 120 miles southwest of Berlin. The wood was intact because it was buried in waterlogged soil where fungi and bacteria — organisms that usually cause wood to decay — could not survive.

Tegel is an expert in a technique known as dendrochronology, which takes advantage of distinctive patterns in tree rings to determine the ages of wooden objects. The method involves comparing the ring patterns in ancient wood to historical reference patterns for a certain region; each time period is unique because the shape and width of the rings varies due to climate and other environmental factors. By establishing a historical match for the outermost ring under the bark, scientists can surmise the year when a tree was chopped down.

The method provides a more precise age for wooden objects than carbon-14 dating, which relies on measurements of a radioactive isotope and can pinpoint the time of a tree’s death to only within about 100 years, Tegel said.

Most of Tegel’s research involves analyzing ancient tree rings to understand climate conditions long ago. Although dendrochronology is being used more and more by archaeologists, it can’t be used in all cases because it’s relatively rare to find wood preserved well enough to be analyzed, he said.

Tegel and his collaborators examined 151 oak timbers used to make the newly discovered wells and concluded that the trees were felled between 5469 and 5098 B.C. They also determined that at least 46 trees contributed to the material. These trees were up to 300 years old when harvested, and some were up to 3 feet in diameter.

The builders of the wells chopped the trees down with a stone adz, a wedge used in the manner of an ax, making cuts just above breast height, the team wrote. They then used wooden mauls and wedges to split the wood into planks and further shaped it using fire and tools.

The wells were constructed with "tube-like" sections made from hollowed-out tree trunks. They also had body chambers that were built out of carefully engineered interlocking logs.

"These kinds of corner joints and connections between the wood were very sophisticated," Tegel said.

Such complexity had been unexpected, he added, because the early farmers who built them did not have metal tools.

Princeton archaeologist Peter Bogucki was enthusiastic about the find. "This is a super discovery that give us a whole new insight into the lives on these early farming settlements," he said.

Bogucki and other experts in European prehistory noted that similar wells had been found before. But Bogucki said those had not been as closely studied, and didn’t reveal such "amazing contents."

The researchers found items that had been cast into the wells, including wheat and remnants of peas, lentils, apples, raspberries and hazelnuts. They also unearthed bone and stone tools and a large amount of pottery. Some of the ceramic items had been repaired and decorated with a resin material, suggesting the vessels were reused for many years.

The team also discovered the remains of two young pigs that appeared to have been deliberately placed — both were found in the exact same position — in the excavation pit of one of the wells, Tegel said.

"The stuff in the bottom of the well is a nice little time capsule," Bogucki said. "To be able to find traces of these plants and organic materials and repaired pottery is astonishing."