You don't need to swim, snorkel or dive to see the Canary Islands' underwater world — you can watch it drift past through a glass floor, or descend beneath the waves in a real tourist submarine. These gentle, effortless trips are among the most family-friendly things to do on the islands, letting grandparents and toddlers alike peer into the clear Atlantic without so much as getting their feet wet. The volcanic seabed drops away into wonderfully clear water full of fish, so even a short trip out from a southern marina rewards you with a proper look beneath the surface.
Here's what each experience involves, what you'll actually see, and why they're such a hit with families.
Glass-bottom boat trips
The simplest and cheapest option: an ordinary-looking boat with a viewing well or glass panels set into the hull, so you can look straight down into the sea as you cruise. Trips typically potter out from a resort marina along the coast, pausing over rocky reefs and sandy patches where fish gather, often near a spot where the crew scatter a little feed to bring the shoals in close. Many trips combine the underwater viewing with a scenic coastal cruise and a swim stop in a sheltered bay, so you get a relaxing half-day on the water as well as the marine life.
They sail from marinas all around the islands, but the busy southern resorts have the most choice — the boats at Puerto Rico and Puerto de Mogán on Gran Canaria, and the southern Tenerife marinas, run frequent trips and often bundle in a hop along the coast to a neighbouring resort.
The tourist submarine
For something more special, a genuine passenger submarine operates off the south of Gran Canaria, diving with sightseers aboard to give a true below-the-surface experience. You board at the marina, descend a ladder into the pressurised cabin, and the sub sinks beneath the waves — each passenger gets their own porthole to watch the seabed, fish and sometimes a sunken wreck glide past in the blue-green light. It's a real submarine dive, not a boat with windows, and that novelty makes it a genuine highlight for children and curious adults alike.
The submarine is popular and runs limited daily departures, so book ahead, especially in peak season and for morning slots when the light underwater is usually best. Buying online in advance often works out cheaper than at the kiosk — as of 2026, check the operator's official site for current times and prices. If anyone in the group is claustrophobic, the cabin is snug, so the more open glass-bottom boat may suit them better.
What will you see?
Plenty, though set your expectations sensibly — this is the temperate Atlantic, not a tropical coral reef. Expect shoals of bream, damselfish, mullet and other Atlantic species, often in impressive numbers where the crew feed them; rocky volcanic reefs and sandy seabed; and, with luck, a passing ray, octopus or larger fish. Some routes pass a wreck or artificial reef that has become a fish magnet. The water's famous clarity means visibility is usually excellent, so even the glass-bottom boats give a surprisingly vivid show.
These trips depend on calm, clear conditions. On a windy or choppy day the water gets stirred up and visibility drops, and rougher seas can mean queasy stomachs on the smaller boats — if you're prone to seasickness, take a tablet before you sail and choose a settled day. Operators will sometimes postpone in poor conditions; that's a good sign, not a nuisance.
Perfect for families
This is where these trips really shine. There's no swimming ability required, no equipment to master and no scary bits — just an easy, comfortable outing that even young children and less mobile travellers can enjoy, making them one of the best activities for a family holiday. Children are usually captivated by watching the fish appear at the glass or the porthole, and it's a lovely, low-key alternative to a busy theme park or a full day on the beach. Combine a morning submarine dive or glass-bottom cruise with an afternoon at the beach and you've got a varied, everyone-happy day out.
How it compares to snorkelling and diving
If you and your family are confident in the water, snorkelling straight off a calm beach or booking a try-dive will get you closer to the fish for less money — see our guide to boat trips and watersports for the active options. But for non-swimmers, nervous travellers, small children and anyone who simply wants to stay warm and dry, the glass-bottom boat and the submarine are unbeatable: all the wonder of the underwater world, none of the wetsuit.
Is it worth it?
For families and anyone who won't or can't get in the water, yes — the submarine in particular is a memorable novelty children talk about for weeks, and even the humble glass-bottom boat turns a coastal cruise into something the whole family enjoys. Manage expectations (Atlantic fish, not a coral reef), pick a calm day, and book the submarine ahead. For more easy, family-friendly ideas, browse our full list of things to do.