Argentina Rafting have been putting people on the Río Mendoza for more than thirty years, which on this river makes them one of the founders rather than one of the newcomers. The runs are on the stretch below the Potrerillos dam, an hour west of the city, where snowmelt off the Andes keeps the water cold and fast through the summer.
The standard half-day is a grade II–III run with a guide in each raft, and they add kayaking, canyoning and horse rides for anyone making a day of it. Their guides hold international white-water rescue certification, which is worth asking any rafting operator about and which this one volunteers.
They publish no street address; the pin marks Potrerillos, where the trips run from. Book on WhatsApp — most operators here send the pick-up time and meeting point the same way.