Vinland is a term used by Vikings to refer to what historians believe is North America. There are no borders of Vinland, as it was not a country, but just a term for a general area. The term is said to be used to describe the area around Newfoundland and Labrador.

The most- well known establishment in Vinland is L'Anse aux Meadows, which is in northern Newfoundland.

So, all in all, one cannot show "how big" Vinland is, as it was not a political entity, nor a fully defined region.

Also, did they have any territory on Greenland?