The Maratona BTT Piranhas do Alqueva begins and ends at Parque da Cidade de Reguengos de Monsaraz, located in Portugal's Alentejo region. This mountain bike marathon offers two distances: a 70 km race for those prepared for moderate technical and physical challenges, and a 50 km half-marathon with less difficulty.
The event is included in the Alentejo BTT 4Marathon Series, allowing participants to compete for overall standings and awards throughout multiple races. Both men and women aged 15 and above may participate, with the full marathon restricted to riders 18 years or older. Separate categories exist for E-Bikes. The courses are clearly marked, featuring aid stations, mechanical support, and safety personnel.