Created by the fusion of six enormous shield volcanoes, Isabela is the largest island in the Galápagos, making up about half the total surface area of the archipelago. Today, we visited an area called Urbina Bay at the western base of the Alcedo volcano.  

Urbina Bay is a fascinating site of great geological and historical interest. In 1954, an area of marine reef (about 1.5 square kilometers) was uplifted almost instantaneously by as much as 15 feet, leaving many marine creatures exposed. During our hikes this morning, we were able to see the evidence of this occurrence. We also saw some giant tortoises, a dome-type population, in addition to three species of land iguanas, eating and warming up in the sun.  

Many years ago, Isabela was the focus of a major program in the ecological restoration of the islands. Supported by Lindblad Expeditions-National Geographic through guest donations, the Isabela Project sought to eradicate feral goats and donkeys. The large-scale project was successful beyond all hopes and now the native inhabitants—mostly iguanas and tortoises that once faced extinction—are well on the road to recovery.    

After hiking and a refreshing swim on the landing beach, we returned to the ship, where one of our naturalists, Carlos, enlightened us about Charles Darwin and his time in the Galápagos and its impact on the formation of his theory of natural selection.  

In the afternoon we repositioned the National Geographic Endeavour a few miles north to visit the historic bay of Tagus Cove. This area of Isabela was one of the places Charles Darwin visited in 1835. Today some interesting historic graffiti can be found, dating from the time when buccaneers sought a sheltered harbor here.  

Some of us spent the afternoon kayaking and deepwater snorkeling. Others hiked up to the rim of a tuff cone overlooking Darwin Lake or took a Zodiac ride along the fascinating coastline, where we found penguins, flightless cormorants, and other surprises.