Rubblework is masonry of unhewn, naturally shaped stones. The masonry style in this picture uses mortar to bind them together to support the multiple levels. It is a boundary wall with a fence on top of it.
Is this the bulwark of a castle? Or is it a boundary of a medieval cathedral? Close. This is more modern in its construction (1951-1952), and hidden behind this wall is Saint Barnabas Anglican Church. It's construction certainly makes it look like it has been there for centuries and implies there is history behind it. For interest, St. Barnabas has been at multiple locations in Victoria and was originally established circa 1860.
While angles and converging lines have grabbed Vince's attention, it was the multiple levels and the dual effect that drew Vince to this location.