Nobody makes isthmuses. They are naturally-occurring geological formations.
Costa Rica is part of the Central American isthmus, Panama makes up most of the isthmus that connects South America to Central and North America.
An Isthmus is a narrow strip of land that connects two larger bodies of land with water on both sides. The Isthmus of Panama, Isthmus of Corinth, Isthmus of Perekop, Isthmus of Gibraltar, Isthmus of Suez are all examples
The Isthmus of Panama connects South America with countries north of Panama. The Isthmus of Panama is located in Panama, which is part of Central America.
Isthmus of Panama, Central America - the isthmus joining North America and South America, Isthmus of Corinth - a narrow isthmus between the Gulf of Corinth and the, Isthmus of Kra - a narrow isthmus linking the Malay Peninsula to the Asian
The Isthmus Of Panama.
A canal
Isthmus of Panama
The Karelian Isthmus
isthmus Clark
isthmus of kra
Isthmus of Panama
Survey Isthmus