Courir entre deux O is a late-November race series in Caen, featuring three running races with a total participant cap of 1,500. Now in its 20th edition, the event maintains a practical local-race setup: runners must register in advance, as race-day sign-ups are not permitted.
The program also includes a 10 km pedestrian hike, open to participants aged 16 and over, with on-site registration available before the race weekend. A bib exchange is offered for runners. FFA-licensed athletes must present a valid license copy, and non-licensed runners must provide the required PPS document from the FFA website.