Complex sentence: Dwyer's nephew, John Donoghue (1822--1892), built The Old Stone House, Molongolo Rd, Bungendore, circa 1865, a huge strongly constructed Bungendore landmark and a monument to pioneering and hard-working Irish Australian settlers.
Split into simpler sentences: Dwyer's nephew, John Donoghue (1822--1892), built The Old Stone House, Molongolo Rd, Bungendore, in circa 1865. This is a huge strongly constructed Bungendore landmark and a monument to pioneering and hard-working Irish Australian settlers.