Rapha is encouraging thousands of women around the world to ride 100km on July 7.
As well as sending 100 female riders to attempt the Etape du Tour sportive, a major mountain stage of the Tour de France on that date, in the year of the 100th Tour, the Rapha Women's 100 aims to 'gather a global community of women to take part in a shared adventure'.
It'll be a fully interactive experience, with women's stories of riding the 100 and plenty of first hand info on training, as well as various events for the day itself to complete the ride.
Visit the Rapha website for more details.
Rapha are asking participants to use the hashtag #womens100 to link up with other riders on Twitter and Instagram, and there's a Strava page too.
Rapha are also running a sale of women’s clothing to celebrate the launch of the Women’s 10.