Complex sentence: The Carretera Central is a historic north--south central highway in Puerto Rico, linking the cities of San Juan and Ponce by way of Rio Piedras, Caguas, Cayey, Aibonito, Coamo, and Juana Diaz.
Split into simpler sentences: The Carretera Central is a north--south central highway in Puerto Rico. The highway runs from the north coast city of San Juan to the south coast city of Ponce via Caguas, Cayey, Aibonito, Coamo, and Juana Diaz.