Experience the Thrill of Boca do Inferno: Half-Day Swim Tour Along Cascais Coastline
Difficulty
moderate
Duration
3–4 hours
Fitness Level
Participants should be in good swimming shape, comfortable with ocean conditions and capable of sustained open-water swimming.
Overview
Discover the rush of swimming 3km along the dramatic Cascais coastline to Boca do Inferno, an iconic natural arch where Atlantic waves crash with fury. Expert guides accompany you on this half-day, adrenaline-filled aquatic adventure near Lisbon.
Boca do Inferno Swim Tour - Half Day (Special Edition)
1/2 day • 3km • Sea
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About This Adventure
Experience an exhilarating half-day swimming adventure along the stunning Cascais coastline. Dive into the legendary Boca do Inferno, a breathtaking natural formation, as you swim 3km between historic landmarks. With expert guides and scenic stops, this unforgettable journey promises both adrenaline and awe in one of Lisbon's premier destinations.
Duration
1/2 Day
Distance
3km
Water Temperature
16ºC - 22ºC (61ºF - 72ºF)
What you'll do
An adrenaline rush, an unforgettable swimming experience in a scenery of spectacular beauty.elcome to Cascais, the premier holiday destination of the Lisbon coastline.
Come swim to one of the most famous and feared holes in Cascais, Boca do Inferno, also known as “Mouth of Hell”. It is believed that this place was once a cave that with time and the force of the sea gave way and gave rise to the scene as it is known today. Currently, Boca do Inferno is an open-air cavity, with a kind of arch through which the sea water enters.
This adventure takes you to explore the Atlantic coast, swimming along the rocky route between the Fort of Nossa Senhora da Guia and the Santa Marta Lighthouse, making small stops to see the amazing scenery that characterizes the region.
What's included
Safety
- Personal Accidents Insurance
- Accompanied by experienced guides
- Boat and kayak support
Food
- Water bottle and typical cake from the region
Others
- Photos
What's not included
- Equipment
Your itinerary
The most feared hole of Cascais We meet at Marina de Oeiras from where we will depart by boat to Cascais.
Arriving in Cascais, we will start our adventure, swimming about 3km to Boca do Inferno.
We will end this unforgettable experience with a boat trip back to Oeiras.
Adventure Tips
Check water temperatures
Expect Atlantic temperatures between 16ºC and 22ºC; wear a wetsuit during cooler months for comfort.
Use provided boat support
Take advantage of kayak and boat assistance to rest or catch your breath during the swim.
Start well hydrated
Drink water ahead of time and pack energy snacks; the swim is demanding, and hydration is key.
Arrive on time at Marina de Oeiras
Punctuality ensures a smooth boat transfer to Cascais, where your swim begins.
Local Insights
Wildlife
- Seagulls commonly seen along the coast
- Occasional sightings of dolphins near the swim route
History
Boca do Inferno has been shaped over centuries by the persistent power of the Atlantic, once a cave transformed into an open sea archway featured in local lore.
Conservation
The area is protected under regional coastal regulations to preserve its natural state and minimize impact from tourism and ocean activities.
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Adventure Hotspots in Lisboa
Frequently Asked Questions
Recommended Gear
Wetsuit
Keeps your body warm in cooler Atlantic temperatures during fall and spring.
fall specific
Swim goggles
Protects your eyes and improves visibility underwater throughout the swim.
Swim cap
Enhances visibility and helps keep hair out of your face while swimming.
Waterproof sunscreen
Protects your skin from the strong Atlantic sun during summer swims.
summer specific