Uganda's Joshua Cheptegei smashed the men's 10,000m world record as Ethiopia's Letesenbet Gidey broke that of the women's 5,000m in Valencia.
Cheptegei, 24, clocked 26 minutes 11.00 seconds to beat Kenenisa Bekele's 15-year-old time by more than six seconds.
Gidey, 22, clocked 14 minutes 6.62 seconds to better the 14mins 11.15secs set by Tirunesh Dibaba in 2008.
They achieved the feats at the NN Valencia World Record Day, a one-off event taking place in the Spanish city.
"I'm happy," said Gidey, who won 10,000m silver at the 2019 World Championships in Doha. "This has been a long-time dream. It is very big for me."
Bekele's previous world record time of 26mins 17.53secs had been the longest standing men's 10,000m world record in history.
Cheptegei's success marks his fourth world record in 10 months, having broken the 10km road best in December and the 5km road record in February.
At the Monaco Diamond League in August, he broke another of Bekele's world records, beating his 16-year-old mark in the 5,000m by two seconds.
The World Record Day, in which both Cheptegei and Gidey had pacemakers, took place at Valencia's Turia stadium with 400 people present.