An excavation began this week to recover an eight-meter-long (26 feet) dugout canoe from the bottom of Lake Constance in southern Germany.

The water vessel, which is believed to be from 2400-2300 BC, was first identified in the second half of 2018. It is believed to be the oldest known watercraft found in the lake.

"The dugout is one of the most completely preserved prehistoric watercraft ever found," said the Baden-Württemberg Ministry of Economics.

The task to raise the craft from the bottom of the lake will prove to be tricky, owing to the quality of the wood. Ancient canoes that have been found in the area were able to be brought to the surface in one piece, but that cannot happen with this recovery.

"The wood is too fragile and too soft for this," said Stuttgart District President Wolfgang Reimer. The recovery is expected to take several weeks.

What is a dugout canoe?

Dugout canoes are hollow rafts that were primarily used in prehistoric times to transport goods, for fishing on the water, and for transportation. Historians have found evidence of people have been crossing Lake Constance for thousands of years.

"With a dugout canoe, you could get over long distances quickly and easily," Julia Goldhammer told the dpa news agency. "There was a lot more forest and moorland, plus no roads, so water was an obvious choice."

Goldhammer and her colleague, Heiner Schwarzberg from the Archaeological State Collection of Bavaria, believe that there are many more similar canoes in the lake.

"Of course there must be more dugout canoes, after all, there were dozens of prehistoric lake dwellings," said Schwarzberg.

He added that surviving canoes would likely be in good condition, due to the conditions of the lake.

"They are preserved in silt and under exclusion of air, like bog bodies," said Schwarzberg. "That's why Lake Constance is also ideal for finds, because it doesn't decay as quickly here."

kbd/msh (AFP, dpa)