パナマ地峡
In 1501, Rodrigo de Bastidas was the first European to explore the Isthmus of Panama sailing along the eastern coast. A year later Christopher Columbus on his fourth voyage, sailing south and eastward from upper Central America, explored Bocas del Toro, Veragua, the Chagres River and Portobelo (Beautiful Port) which he named. Soon Spanish expeditions would converge upon "Tierra Firma" (also Tierra Firme, Spanish from the Latin terra firma, "dry land" or "mainland") which served in Spanish colonial times as the name for the Isthmus of Panama.