How did they determine where state lines in the U.S. are?

Question

I know rivers and oceans, of course but what about those straight lines?

Answer 1

Some borders are just arbitrary divisions, brought about by political factors and the like.

Sometimes there are interesting stories behind them. For example, in the "Toledo War", Michigan and Ohio fiercely contested a 20 mile-wide strip of land on Michigan's southern border. Michigan insisted that its territory's southern latitude was defined by a line starting from the southernmost point of Lake Michigan, while Ohio insisted their state borders extended north to the easternmost point of Lake Huron, which included the city of Toledo. As a compromise, Ohio got the disputed territory, and Michigan was granted the Upper Peninsula between Lakes Michigan and Superior. In the long run, Michigan got the better deal.

Originally, Wisconsin's border was to likewise extend to the southern foot of Lake Michigan, but this would have prevented Illinois from having a port on the Great Lakes, so the line was moved northward. Otherwise, Chicago would be in Wisconsin.

Answer 2

Some boundaries are physical features such as rivers. And they do flood occasinally and change lines.
Some are original purchase lines from the 1600's 1700's,1800's. We lived on the original Boston Purchase line which they extended all the way across the country.
Surveying is done to get exact locations, but it has to be based on an original mark.

Answer 3

In the eastern US it is mostly natural boundaries (ie lakes, rivers mountains). As the country expanded west and surveying techniques began to modernize, the boundaries were defined by set distances and both latitudinal and longitudinal measures.

Answer 4

All of the straight line state boundaries I have seen are based on lines of latitude and longitude.

Answer 5

what about those straight lines?
They are determined using survey techniques brought over from Europe.