There is a wealth of locations across the valley to explore, and Tafi is a hiker's paradise.
Horseback Riding -- La Morocha Cabalgatas, Galeria Los Arcos, Avenida Presidente Perón (tel. 3867/154-123135 [cell]; www.lamorochacabalgatas.com), will hook you up with some horses to explore the area.
Trekking -- La Cumbre, Av. Presidente Perón 120 (tel. 3867/421768), hosts treks around the lake and climbs to the nearby mountain known as Cerro Pelao. Aucache Expediciones, Felix Sosa s/n (tel. 3867/421378), is another agency that conducts trekking excursions.