Isla Genovesa (Genovesa, or Tower Island) was named after the Italian city of Genova (Genoa), which was the birthplace of Christopher Columbus. It is a relatively small island and only measures 14 km² (5.4 sq mi). Genovesa Island is actually the only part of the rim of a large caldera that rises above sea level. The rest of the caldera and its rim are submerged. The highest point on Genovesa rises 76 m (249 ft) above sea level.

At Darwin Bay you can see thousands of birds, including frigatebirds, swallow-tailed gulls, red-footed boobies, noddy terns, lava gulls, tropic birds, doves, storm petrels and Darwin finches, earning the islands its nickname of 'bird island'. Nazca and red-footed boobies can be seen at the bird-watching plateau of Prince Philip's Steps.

Genovesa Island is also home to a large Palo Santo forest.