ocr: Chile's unusual shape -2,697 miles long andi nowhere more than 112 miles wide - makes air travel indispensable. Internal air routes are well developed; some, including tlights to the Juan Fernandez Islands, are served by air taxis. The Pan-American Highway is Chile's only arterial road, crossing the Peruvian border and running down, via the capital of Santiago,to Puerto Montt. Santiago is notorious in Latin America for its severe congestion. It has one ofthe highest taxi: and bus densities in the world.