Los Túneles: the lava aquarium off Isabela
Ask land-based travellers which single tour was worth the whole trip and the answer comes back, disproportionately, Los Túneles. Off the coast of Puerto Villamil on Isabela, ancient lava flows froze into arches, bridges and calm channels, and the boat trip through them is equal parts geology and aquarium: glassy water, seahorses, whitetip sharks asleep in the tunnels, turtles everywhere. If you are building an island-hopping route, this site is the strongest argument for including Isabela.
What the place actually is
The name is literal: lava tunnels, some collapsed, some still roofed, forming a maze the boat threads at low speed. Above water it is black rock and arches; below it is a sheltered, shallow nursery. The calm water is the point: this is one of the few premium snorkel sites in Galápagos where current is rarely the story, which makes it the trip we recommend to nervous swimmers who still want the headline wildlife.
Wildlife, honestly ranked
- Seahorses: the best site in the archipelago for the Pacific seahorse, hanging in the shallows with its tail curled around coral. Guides find them; look, do not touch.
- Whitetip reef sharks: dozens rest in the shaded tunnels and under arches, close enough that passing over them becomes routine within half an hour.
- Sea turtles: constant, feeding and surfacing around the boat.
- Galápagos penguins: the small colony on Isabela’s rocks sometimes shares the site; they are the world’s rarest penguin, about 2,000 individuals concentrated on Fernandina and Isabela.
- Rays, lobsters, schools of reef fish, and in season the odd mola mola sighting offshore.
Season shifts the cast rather than the experience: the warm months (December-May) bring the clearest water, while the cooler garúa months concentrate marine life and are when penguins are most likely. Our best time guide has the month-by-month split.
How the trip runs
Tours leave from the Puerto Villamil pier, typically in the morning when the sea is calmest, and run about half a day including two or three snorkel stops among the tunnels. The boat ride out crosses open water for part of the way, so if you are the seasick type, take your medication half an hour before boarding; the morning departures ride better than the afternoon wind. Cost runs around $150 per person (check current rates) and most operators include snorkel gear, wetsuit in the cool season, and a snack.
Two rules worth remembering on any such trip: stay two meters from every animal, and follow the guide’s line through the tunnels — the surge inside an arch is the only real hazard of the day. The park rules overview sums up the dos and don’ts that apply everywhere.
Fitting it into a route
Los Túneles needs a full Isabela day: ferry in the morning from Santa Cruz (07:00), tour the next morning, ferry back on a later day. That is why our 5-day land-based itinerary and the 7-day version give Isabela at least two nights. Pairs well with Sierra Negra on the other day: volcano one morning, lava aquarium the next.
Booking note: in high season the good boats fill days ahead, and a slot matters more than the price difference between operators. Galapagos Dana Tours books Los Túneles, the ferry legs and the hotels as one block. And if the islands end your trip, our cloudforest hotel in Mindo is the quiet chapter after the boats: Las Terrazas de Dana.
Last verified: September 2026