SUNDAY's Comrades Marathon holds more dangers than just steep uphills. The road from Maritzburg to Durban can be treacherous in parts, warned race director Johan van Staden.
Uneven surfaces - not potholes - are some of the potential threats, he said. Going down Polly Shortts is particularly bad.
The estimated 19000 runners who will line up before dawn on Sunday in Maritzburg have been told to be especially careful while running in the dark on the 89km route.
"Down Polly Shortts there are no street lights," Van Staden warned the lead runners. "We've put temporary lighting up all the way down Polly Shortts up to Ashburton. By the time the slow runners reach that point the sun will be coming up and they will be able to see (the road clearly).
"Roadworks are not really affecting us. The area that is of concern is Cato Ridge - there are a couple of big holes there," he said.
"And we have plans to fill and level up the road unevenness the night before the race."