FERNANDINA, lying west of Isabela and dominated by the brooding shape of Volcán La Cumbre (1476m), is the youngest island in the archipelago, thought to be between 60,000 and 400,000 years old. It’s also one of the most volcanically active islands, erupting ten times in the twentieth century alone, and most recently in April 2009. La Cumbre is crested by a huge caldera, 6km wide and 900m deep, the floor of which exploded in 1968, sending it crashing down by 300m. Fernandina has so far escaped the introduced species that have so damaged other islands, leading to the claim that it’s the world’s largest pristine island; take care you’re not inadvertently transporting any organisms, such as seeds, on your clothes or the soles of your shoes.

Punta Espinosa, a spiky finger of lava at the northeastern tip of the island, is Fernandina’s only visitor site. It’s home to a sizeable colony of marine iguanas, their ashen bodies crammed head to foot on the black rocks. They lay eggs in pockets of sand and you’ll see Galápagos hawks in the trees nearby waiting to pounce on any stray hatchlings. This is one of the best islands for flightless cormorants, which stand at the water’s edge after a foray for food underwater, to dry out their useless wings. The Galápagos penguin can also be seen floating around the point, competing for fish with sea lions.

A trail here leads over rippled pahoehoe lava, studded with clumps of lava cacti, to a series of tide pools, a great place to spot crabs, octopuses and a range of shore birds, including whimbrels, herons and oystercatchers. A final trail heads eastwards to an imposing wall of aa lava, a jagged barrier to the slopes of Volcán La Cumbre.