The largest island in the archipelago, built from six volcanoes. Sierra Negra, the Cabo Rosa tunnels, the Wall of Tears and the Tintoreras channels, plus penguins at the equator.

A long day and a 2.5-hour crossing to Puerto Villamil: the Arnaldo Tupiza tortoise breeding centre, the flamingo lagoons, and 45 minutes of snorkeling in the channels of Tintoreras Islet.
Extra fees paid on the day and not included: water taxi USD 1 in Santa Cruz and USD 1 in Isabela; Isabela entrance USD 10 for foreign visitors, USD 5 for nationals.

The fumaroles and sulfur deposits on the flank of Sierra Negra, in a dry tropical landscape of birds, tortoises and iguanas.

Sierra Negra rises 1,124 m above sea level, 22 km from Puerto Villamil. Horses skirt the eastern rim of the caldera to Los Jaboncillos, and from there it is on foot to Volcan Chico and the sulphur mines.
Come prepared for heavy rain or drizzle. In fog the group must stay together at all times and note landmarks in order to retrace the route.

A half day walking out of Puerto Villamil past 2.5 km of white-sand beach, lagoons and mangroves to the lava wall built by prisoners of Isabela's penal colony between 1946 and 1959.

Three hours off Puerto Villamil in three parts: a panga ride around the islets, a walk over lava flows past resting white-tip sharks, and a snorkel over rays, turtles and reef fish.
Bring swimsuit, sandals or water shoes, towel, sunscreen, bottled water and a cap.

Four to five hours out of Puerto Villamil to the lava arches of Los Tuneles, with a first stop at Roca Union in open water for boobies, pelicans and sea lions.

An excursion into a volcanic area of Isabela shaped by lava fields and rock formations, where different ecosystems have taken hold on the old flows.