The Isthmus of Tehuantepec () is an isthmus in Mexico. Southern Thailand consists of the narrow Kra Isthmus that widens into the Malay Peninsula. It was situated upon a rocky peninsula, connected with the mainland by a narrow isthmus. Another example is the Welland Canal in the Niagara Peninsula (technically an isthmus). Francisco Pizarro had accompanied Balboa in the crossing of the Isthmus of Panama. They were separated by a wall, which traversed the La Pared isthmus. The fortress of Koivisto provided similar support from the southwestern coast of the Isthmus. Today the connection is formed by a narrow sandy isthmus. The Capitol is located at the southwestern end of the Madison Isthmus. They are separated by a narrow isthmus of gravel. The Karelian Isthmus, North of the city, is a popular resort area. The Isthmus of Perekop /Perekop/Or Qapi, about wide, connects Crimea to the mainland. Maury also advocated construction of a railroad across the Isthmus of Panama. Most of these roadways are in the Papaloapam, Mixteca, Isthmus and Coast Regions. The Isthmus of Panama was placed under its jurisdiction.