Jan Roelof Kruithof

Jan Roelof Kruithof was a Dutch marathon speed skater nicknamed the Diesel of Havelte, remembered for long-distance strength on natural ice and for nine victories in the Alternatieve Elfstedentocht. He was born on 16 December 1936 into a farming family in Ouwsterhaule in Friesland. At four his family moved to a farm in Kolderveen in southwest Drenthe. After primary school he trained as a carpenter, worked in construction, earned a contractor diploma in 1956, and later completed an eight-year evening course as an architect, finishing in 1969. In 1965 he opened his own architectural practice in Havelte, the town that gave him his lasting nickname.

He began intensive marathon training only in his early thirties, after earlier tourist rides in the Elfstedentocht of 1956 and a 1963 race finish outside the time limit. Coach and former champion Jeen van den Berg urged him to refine technique after spotting him at Thialf. From the early 1970s he dominated races longer than 100 kilometres. He won early international marathons in Sweden and then became the signature winner of the Alternatieve Elfstedentocht, taking the 200-kilometre event nine times across Norway, Finland and North America between 1974 and 1984. On Dutch natural ice he won eight classics, including four Oldambtrit titles (1969, 1976, 1978, 1980), two Hollands Venetiëtocht wins, the Noordwesthoekrit in 1985 and the Veluwemeertocht in 1987 at age fifty.

The official Elfstedentocht eluded him in his peak years because no race was held then. When it returned in 1985 he finished twelfth after falls while walking between ice sections at Kimswerd; in 1986 he placed fifty-second; in 1997 he finished among the first tourist riders. He twice held the unofficial world hour skating record (Assen 1973 and Inzell 1976) and in 1994 set a 24-hour distance mark of 655.6 kilometres at Baselga di Pinè that stood for thirty-one years. The KNSB awarded him its Golden Pin on his eighty-first birthday, and Havelte unveiled a commemorative stone in 2023.

Away from the ice he remained an architect in Havelte. He was married for fifty-two years to Jantina Kruithof-Olie, who died in 2013; they had two children. His family announced his death on 3 October 2026. He was eighty-nine. Dutch public broadcasters and skating media remembered a relentless endurance champion whose best years coincided with a long Elfstedentocht drought, and whose diesel stamina made him a folk figure of natural-ice marathon skating.