Main Festivals of Horta de Sant Joan Activity · Horta de Sant Joan, Terra Alta, Tarragona Image of Horta de Sant Joan, not of the place itself. The main festivals of Horta de Sant Joan, the town that inspired the young Picasso. 4-13 de setembre Photo: Hans Hillewaert (CC BY-SA 3.0) What to see and do in Horta de Sant Joan