Around 500 runners from 32 countries will run along the 160-kilometre path where the Berlin Wall once stood.
Hundreds of runners set off for a poignant ultra-marathon on Saturday: a 160-kilometre route around where the Berlin Wall stood.
The race comes amid a host of commemorations marking 30 years since the collapse of the communist bloc.
One of the most important symbols of the division between communist and capitalist Europe was the Berlin Wall.
It fell in November 1989 and while for some participants the race is all about the physical challenge, for others it’s about remembering the 138 people that were killed trying to get to the west.
The route goes through the Brandenburg Gate and Checkpoint Charlie, as well as passing monuments to the wall’s victims.
Little of the original wall remains with the longest single section being the kilometre-long East Side Gallery, which is now covered in art and serves as a popular backdrop for tourists taking selfies.
For its 8th edition, some 500 participants — comprising 32 different nationalities — started running at 6 am CEST.
The most seasoned will have to run all Saturday night before completing the test in the early hours of Sunday.
The standing record was set by UK's Mark Perkins in 2014 at an impressive 13 hours and six minutes.
"What really impresses me is the number of participants, because the wall's history is important to them," said Nina Blisse, a race organiser. "Many do not do it to run fast, they read every memorial along the way."
Each year, one Wall victim receives a special tribute with their face featuring on medals. A ceremony is held at the spot where they died.
In 2011, when the first race was held, Chris Gueffroy — the last person shot dead on the Berlin Wall was honoured.