depending on which Washington you mean either 2 or 3 if not 4 major ones
but many less important ones too in either case
Columbia River, Oregon.
Yes
Europe has many boundaries and borders, but Europe as a land mass stretches from the Hebrides and Iberian peninsula in the west all the way to the Polish - Ukrainian border in the north east and the Romanian - Turkish border in the south east.
Border .
Natural boundaries are coastlines, mountain ranges, lakes, rivers, gulfs, canyons, desert wastelands... basically, a part of the earth that is considered by most to be uninhabitable. Political boundaries are the borders that are represented on maps by all the other lines besides natural boundaries and latitude/longitude indicators (although many political boundaries are natural boundaries and parts of lines of latitude and longitude). They are the boundaries between nations and between national subdivisions.
It is entirely within the boundaries of Arizona.
In some places fences run the boundaries, in many others ,especially in Europe, there are no visible boundaries except at Border Posts.Answer 2The normal method, in Europe at least, where borders are on land (not along rivers or lakes) is by border stones. These are similar to milestones or boundary stones marking property boundaries. They are place by mutual agreement of the two countries. The border officially runs in a straight line from one border stone to the next one. The border stones are usually within sight of each other.
he as
the Philippines and the Pacific plates border Japan
the eastern border of the Louisiana territory is the Mississippi River
no
There are no counties that border Antarctica -- it is surrounded by the Southern Ocean.