Complex sentence: The decorations on the outer walls of the inner courtyard were made in Plateresco style by Castilho: the arcades include traceried arches that give the construction a filigree aspect.
Split into simpler sentences: The decorations on the outer walls of the inner courtyard were made in Plateresco style by Castilho. This ornamentation on the walls and the traceried arches of the arcades give the construction a filigree aspect.