Argentine Patagonia consists of the southernmost provinces - Chubut, Neuquen, R�o Negro, Santa Cruz. The island province of Tierra del Fuego is a bit of a special case - nominally not part of Patagonia but to all intents and purposes it is. Same for Chilean Patagonia - the two regions of Aisen and Magellanes (which includes Chilean Tierra del Fuego).
Patagonia taken as a whole is a huge, mesmerising place - great extremes of landscape, habitat, flora and fauna, though the popular impression of bleak mile after bleak mile of emptiness is certainly true of much of it - and utterly complelling to see and travel through. Down the spine of the Andes, the lake district is ridiculously beautiful. The glacial south of Chile is incredible. And while there is a significant Welsh community centred on the towns of Gaiman, Trelew and Trevelin in Chubut, they remain a small part of the wider society. (Sorry for going on, I'm a bit of a fan!)