Britain's Lizzie Armitstead triumphed in a sprint finish to win the women's Tour of Flanders for the first time.
Fellow world champion Peter Sagan won the men's race with a solo victory.
Armitstead, who rides for the Boels-Dolmans team, edged out Sweden's Emma Johansson to win her race, which is now part of the Women's WorldTour.
The pair broke clear on the final climb. A group of nine were unable to chase them down and Armitstead triumphed in a long sprint to the line.
It is the 27-year-old's fourth win of the season after success at Omloop het Nieuwsblad, Strade Bianche and Trofeo Binda.
Sagan was 25 seconds clear of three-time winner Fabian Cancellara, who was competing in his final Tour of Flanders, with Sep Vanmarcke third.
The Slovakian dropped Vanmarcke on the Paterberg, the tough cobbled ascent that has a maximum gradient of 20%, then held off Cancellara's challenge, increasing his lead in the last 5km of the 255km race.
Britain's Luke Rowe was fifth, 48 seconds behind Sagan, with fellow Welshman and Team Sky colleague Geraint Thomas 12th.
1. Lizzie Armitstead (GB) 3:43.27
2. Emma Johansson (Swe) same time
3. Chantal Blaak (Ned) +2secs
4. Megan Guarnier (USA) same time
5. Elisa Longo Borghini (Ita) same time
6. Eleonora van Dijk (Ned) same time
7. Annemiek van Vleuten (Ned) same time
8. Pauline Ferrand Prevot (Fra) same time
9. Claudia Lichtenberg (Ger) same time
10. Katarzyna Niewiadoma (Pol) +8secs
1. Peter Sagan (Tinkoff) 6:10:42
2. Fabian Cancellara (Trek)+25secs
3. Sep Vanmarcke(LottoNL) +27secs
4. Alexander Kristoff (Katyusha) +48secs
5. Luke Rowe (Team Sky) same time
6. Dylan van Baarle (Cannondale) same time
7. Imanol Erviti (Movistar) same time
8. Zdenek Štybar (Etixx - Quick-Step) same time
9. Dimitri Claeys (Wanty) same time
10. Niki Terpstra (Etixx - Quick-Step) same time