He progressed from animals to motor vehicles to buildings. Wiltshire has been featured in several documentaries on the BBC, including "Fragments of Genius" in which the BBC filmed him flying over London then creating a meticulous, to-scale drawing of the city within three hours.
He has created similar aerial illustrations, including one of Tokyo on a 10-meter long sheet of paper.
Entirely from memory. Again, ENTIRELY FROM MEMORY.
His artwork has been shown all over the world, and he has his own personal gallery in London in addition to multiple published books. The third, "Floating Cities" (1991) made the London Sunday Times Bestseller List.
PS - His birds-eye panorama of Rome may just be my favorite of his aerial skylines. The store section of his website is one that keeps you clicking through. Some pieces appear in color, some are oil paintings and some are simple black and white sketches. But all are amazing. I'm not much for art made after 1750, but I'm now Wiltshire's newest fan.