Roman site of Bílbilis Nature · Calatayud, Comunidad de Calatayud, Zaragoza Celtiberian city of the Lusones that Augustus raised to a municipium with the name Augusta Bilbilis. It preserves a forum, a theatre for some 4,500 spectators and baths decorated by Italic workshops. It went into decline in the second century and was left depopulated in the third. siglo I a. C.-siglo III Photo: Cruccone (CC BY-SA 3.0 es) What to see and do in Calatayud