Located at the foot of the Corcovado and part of Tijuca National Park, Rio’s Botanical Garden is among the finest in the world. Founded in 1808, it comprises 134 cultivated acres, plus 205 acres of tropical rain forest. The garden is part of the Atlantic Forest ecosystem that extends down the east coast of Brazil and that, in 1832, moved a young Charles Darwin to raptures: “Delight ... is a weak term to express the feelings of a naturalist who, for the first time, has wandered by himself in a Brazilian forest,” he famously wrote in his book “The Voyage of the Beagle.” From the entrance, a pathway extends down an incomparable 765-yard avenue of 134 imperial palms. Besides the open gardens, numerous glasshouses are dedicated to bromeliads, orchids, succulents and carnivorous plants. For many of Rio’s inhabitants, this natural splendor is a defining glory of their city.