Lehigh County Map

Cities in between counties

Why are some cities like Bethlehem PA inside two counties, Lehigh and Northampton, and not just in one. Take NYC for example, why cant they make it 1 large county? Or when there is a city between states like Kansas City, Kansas.
If you look at a municipality or outline map of Manhattan, Kansas, it has at the NW corner a loop and a part shooting in, POINT?

First of all Kansas City is not into two states. There are two distinct cities, each with its own city council and mayor. One is in Kansas and one is in Missouri, even though they have the same name.

Counties were laid out early in the state’s history. Bethlehem grew to the point it had to cross the county line that was already established.

Modern day New York was established when New York (which then was only Manhattan) merged with almost 100 different towns in different counties. The counties within New York City are relics only having district attorneys and courthouses. Those counties don’t have commissioners and sheriffs.