El Yunque is the only tropical rainforest in the United States' national forest system, draped across the Sierra de Luquillo mountains in northeastern Puerto Rico. Its highest slopes catch as much as six metres of rain a year, feeding giant tree ferns, vine-hung trunks, and ridgelines that stay wrapped in cloud from morning to night. The Spanish crown set this forest aside as a reserve in 1876, making it one of the oldest protected woodlands in the Western Hemisphere, and the Taíno held the range sacred long before that — the throne, they believed, of the good spirit Yúcahu, whose name the forest finally took in 2007. Four distinct forests stack up its flanks as you climb, from tall tabonuco near the base through palo colorado and sierra palm to a wind-bent dwarf forest of gnarled, moss-choked trees on the highest ridges.
Trails drop to the La Mina and La Coca waterfalls, which slide over dark, mossy rock into pools cold enough to catch your breath, and climb to the stone Yokahú tower, where green hills roll unbroken to the coast. As dusk falls the forest fills with the two-note "ko-kee" of the coquí, the fingernail-sized frog that Puerto Ricans hear as the voice of the island itself. Overhead, the iguaca — one of the world's rarest parrots — is clawing its way back, after Hurricane Maria tore through the canopy in September 2017 and cut the wild flock to a few dozen birds. The forest has largely healed since the storm, and the main road along Route 191 is open again, free to enter through the day. Standing beneath a falling curtain of water to breathe the wet, green air is as close as the Caribbean comes to walking inside a living cloud.