Yelena Nikolayeva wins at the 1996 Olympic Games (© Getty Images)
Two women share the world 20K best time of 1:27:30 and both are among the entries for the first ever IAAF World Cup women's race at this distance.
Nadezhda Ryashkina (RUS) and Liu Hongyu (CHN) both have good recent form. Ryashkina, since 1990 the world track walk 10,000 record holder, comfortably won the 1999 Russian winter championships in Adler with her world best. This was by far the best 20K race of the year. Liu, who clocked her 1:27:30 in 1995, won the Asian Games 10,000 title at the end of last year.
Ryashkina and Liu are the best contenders on paper and their countries may well battle out the Eschborn trophy, where three women will comprise a scoring team.
Russia have five of the six quickest women of the year, and besides Ryashkina have entered arguably the most successful woman race walker in history - Olympic Champion Yelena Nikolayeva, who was second in Adler. Less is known about the current form of the Chinese squad, though it does include two former World Cup winners - Gao Hongmaio and Wang Yan.
Belarus, Hungary and Romania also have strong teams.
Competing at a longer distance than usual is the reigning European Junior 5000 Champion Claudia Iovan (ROM), who set a new world indoor 3000 record this winter.
At the other end of the experience scale comes multi-Australian Champion Kerry Saxby-Junna, now 38. Eleven years ago she became the first woman to walk 20 kilometres in less than 90 minutes, but is still a force in race walking. She tops the world rankings so far this year at 10K.
Mark Butler for the IAAF