New Ankh
Broadly speaking, the generic name for all the suburbs, businesses, streets and homes that have overspilt to the other side of the current city walls. The visual evidence from The Streets of Ankh-Morpork is that overspill development has mushroomed all around the City, save on the seaboard side... as Stephen Briggs has said How much of the city should I show? A million people live in Ankh-Morpork. A walled city big enough to hold them all would be uninteresting, given that much of the action takes place in the Shades or the main civic areas. But all walled cities, especially in times of peace, had suburbs growing up outside their walls. That's how cities grow. In the books, nothing much happens outside the walls; as Terry said, I realised I didn't have to map the whole of New York, only Manhattan".
(Stephen Briggs, quoted from the pamphlet accompanying The Streets of Ankh-Morpork)
New Ankh, then, is the rest of "New York", but we really don't know how far into the state it extends or whiether it crosses the state boundary into New Jersey. The Mappe just shows the beginnings of unnamed streets on all sides, shading into obscurity: and apart from occasional tantalising mentions of people or organisations with names like the Ninja Morrismen of New Ankh, Terry hasn't really said anything much yet.
Some businesses, such as Mr Harry King's recycling plant and compost heaps, necessarily have to exist outside the City walls, not only because of the space they take up but because of the inevitable smell. The books are vague on location, suggesting Sir Harry King's profitable but noisome business concern is located in New Ankh. Contrary to previous speculation, The World of Poo very firmly places Sir Harry King's base and recycling plant outside the walled city, but on the River Gate end of the Ankh, Rimwards of the city.
Still, it's all very fertile turf for fan fiction.....