The word means very top of the summit it is also name a city in Illinois Kansas and west Virginia?

The word you are looking for is "Apex". It means the highest point of something, such as a mountain or hill. It can also be used to refer to the highest level or degree of something, such as "the apex of human achievement".

Apex is also the name of several cities in the United States, including Apex, Illinois, Apex, Kansas, and Apex, West Virginia.