Spain's Third Largest Main Square Curiosity · Ocaña, Mesa de Ocaña, Toledo Image of Ocaña, not of the place itself. Because of its size, the Plaza Mayor of Ocaña is commonly cited as the third largest main square in Spain, behind only those of Madrid and Salamanca, a surprising scale for a town of its population. Photo: Rowanwindwhistler (CC BY-SA 3.0) What to see and do in Ocaña