Tijuca Forest: The World's Largest Urban Rainforest

32 square kilometers of mountainous rainforest in the heart of Rio. Almost entirely replanted in the 1860s after coffee farming stripped the hills bare. That this towering, dense, bird-loud forest is 160 years old rather than ancient should be taught in every environmental science class.

Enter through Parque Lage near Jardim Botanico. The trail to Pico da Tijuca — 1,022 meters, the park's highest point — is about six kilometers one way, steep, through forest so thick sunlight reaches the floor in coins and slivers. Bromeliads on every branch, orchids without looking hard. The humidity is drinkable. Cicadas, frogs, the ascending scale of a screaming piha piercing the canopy like a needle.

At four kilometers the forest opens onto rocky outcrops with views south toward Lagoa Rodrigo de Freitas and the ocean past Ipanema. The final ascent involves metal ladders and handrails bolted into rock. The summit: Rio in every direction — bay, beaches, mountains, the forest below like a green carpet thrown over the city's bones. Sugarloaf to the southeast, Cristo to the south.

Park opens at eight. Bring two liters water, trail shoes with ankle support. Afternoon rains are common in summer. Go slowly. This forest was dead once and people brought it back.