The Triathlon Côteaux du Vendomois - M is a 54.5 km triathlon held at the Villiers-sur-Loir lake in Loir-et-Cher, taking place during a late-May racing weekend. The M race begins in the afternoon and is open to solo competitors or relay teams, positioning it as part of a broader club event rather than an isolated single-distance race. US Vendôme Triathlon is the organizer of this series, now in its 29th year, with the most recent edition attracting over 2,500 participants throughout the weekend.
The schedule includes youth races for the youngest categories, alongside XS, S, M, and L triathlons, as well as an L-distance swim-bike event. The M distance is positioned between the shorter, sprint-like options and the longest event. A notable additional challenge is the VENDÔMAN, where dedicated athletes complete the S, M, and L triathlons within the same weekend.