This page is full of what I visualize as portadas monumentales: (Control+f and type in portada momumental to take you down to the first of many):
http://www.google.es/imgres?imgurl=http://www.arquivoltas.co... I wonder do we all agree that this is what we are talking about?
We have plenty of these here in Avila, and since we have a lot of Renaissance architecture too, we boast a number of portadas with "amplio dovelaje" - which I remember nearly made me give up translating in the early days of my career!