Isabela is the largest island in the Galapagos, bigger than the rest of the archipelago put together. It feels less polished than Santa Cruz and less official than San Cristobal: the main settlement, Puerto Villamil, is still a sandy, low-rise beach town where sea lions, marine iguanas and travellers share the same slow rhythm.
The island's scale is the draw. Six volcanoes form its spine, with Sierra Negra giving hikers a huge caldera rim and black lava landscapes. Down by Puerto Villamil, boardwalks cross lagoons where flamingos feed, and the tortoise breeding centre explains the conservation work needed to keep Isabela's giant tortoises alive.
Offshore, Isabela gets even better. Los Tuneles and Las Tintoreras are classic Galapagos experiences: lava arches, clear water, white-tip sharks, turtles, rays, penguins if you are lucky, and blue-footed boobies nesting on black rock. It is more expensive and less convenient than the central islands, but the payoff is real.