Santa Fe is by far the oldest of all the Galapagos Islands. Geologists estimate it to be at least 4 million years old. Due to its old age, this island carries a wider variety of endemic species than any other of the Galapagos islands. Some of these species are the Barrington land iguana, the Barrington leaf-toed geckoes, the Santa Fe marine iguana, and the Santa Fe rice rat. In addition, large numbers of sea lions are often found lounging on the beaches of Barrington Bay which makes this island the perfect place to dive with these playful creatures. On the cliffs, many different types of birds can be found such as swallow-tailed gulls, shearwater petrels, and red-billed tropicbirds. This island offers something for everyone as the landscape is picturesque, combining beautiful turquoise water bays with giant prickly pear cactus forests, which is perfect for trekking, snorkeling, and diving.