Explore Catalina Island's Underwater Wonders Aboard The Nautilus Semi-Submarine

Read the full experience

Catalina Island, located off the coast of Southern California, is renowned for its crystal-clear waters and vibrant marine life. The Cloned-Semi-Submarine Excursion aboard The Nautilus offers a unique chance to experience this underwater spectacle without getting wet. Departing from Avalon, the island’s main harbor town, this 45-minute tour invites adventurers of all ages to glide beneath the surface and glimpse the diverse sea creatures and formations that define Catalina’s coastal ecosystem. The Nautilus is specially designed with expansive viewing windows that immerse passengers in the island’s famous kelp forests, rocky reefs, and colorful fish populations. The tour reveals geological features like the volcanic-origin seabed and dense beds of giant kelp that create shelter for species ranging from garibaldi and leopard sharks to the elusive sea hare. What sets this excursion apart in the region is its seamless blend of marine education and accessibility. Unlike scuba diving, which requires certification and physical exertion, this semi-submarine ride is ideal for families, seniors, and anyone keen to explore without getting wet. Guides narrate the excursion, highlighting Catalina’s marine biology and conservation efforts, making it both informative and captivating for visitors. Avalon itself is a charming harbor city that complements the underwater experience with plenty of dining, lodging, and beach options, making it a well-rounded destination for outdoor enthusiasts. The tour operator’s commitment to protecting Catalina’s fragile marine environment is evident through sustainable practices onboard, underscoring the importance of conservation in this unique habitat. From dramatic underwater cliffs to schools of shimmering fish darting through golden kelp, The Nautilus excursion presents a front-row seat to one of Southern California’s most spectacular natural settings. Whether you’re a first-time visitor or a repeat explorer, this tour offers an unforgettable glimpse into Catalina Island’s underwater realms in comfort and style.

Trip highlights

Difficulty

easy.

Duration

45 minutes.

Fitness level

Suitable for all fitness levels including children and seniors

Frequently asked questions

Is this tour suitable for young children?

Yes, the semi-submarine is family-friendly and accommodates children with safe, large viewing windows.

Do I need any swimming or diving experience to join?

No swimming or dive skills are required as the tour stays entirely underwater inside the vessel.

Is the semi-submarine wheelchair accessible?

Accessibility may be limited; check with the operator for specific accommodations before booking.

What marine life can I expect to see?

Expect to see species like garibaldi fish, leopard sharks, and diverse kelp forest inhabitants native to Catalina.

Are refreshments provided onboard?

Food and drinks are typically not provided, so it’s best to eat prior to the excursion.

How do I book tickets for this excursion?

Tickets can be booked online via the provided referral link or at the dock in Avalon on the day of the tour.

Local insights

Wildlife

California Garibaldi
Leopard Shark

History

Catalina Island was designated as a game preserve in 1927, helping to protect its unique marine and island ecosystems.

Conservation

The tour operates with eco-friendly practices to minimize impact on Catalina’s delicate marine habitats, supporting ongoing conservation efforts.

About Catalina Adventure Tours

Catalina Adventure Tours, based in Avalon, California, operates guided tours across Catalina Island that highlight the island’s landscapes, wildlife, and history. The company offers four signature experiences: the Summit Sunset Tour, a one-hour tram ascent aboard The Falcon to 1,500 feet with panoramic views and narrated stories; The Nautilus Semi-Submarine Excursion, a 45-minute underwater observation trip modeled after America's first nuclear submarine with underwater gardens, fish feeding, and seasonal evening missions; the Catalina Island City & Scenic Mt Ada Tour, a 50-minute tram tour aboard The Eagle visiting Mt. Ada and the Catalina Casino; and the Inside Adventure Tour, a two-hour eco-land excursion through canyons and coastline featuring wildlife sightings, the Nature Center, and ancient Native American sites. Guides on each tour provide educational narration about the island’s ecology, cultural history, and conservation efforts. Tours combine comfortable transport, photographic viewpoints, and opportunities to observe species such as bald eagles and the island’s bison herd. The Nautilus offers a unique underwater perspective while tram tours deliver elevated panoramic vistas. Catalina Adventure Tours works within Avalon’s visitor infrastructure and supports preservation by educating guests about local ecosystems. Tour durations and clear descriptions help travelers choose the right experience. With professional guides, established routes like Mt. Ada and dependable vessels such as The Falcon, The Eagle, and the Nautilus, the operation presents a reliable, informative way to explore Catalina Island. Tickets are sold at Avalon ticket booths, partner kiosks, and official websites, with schedule updates posted seasonally for visitor planning purposes.

Base locationAvalon, California

Tours offered10+

Adventure tips

Arrive Early for Best SeatingBoard early to secure a window seat for optimal underwater views during the excursion.

Bring a Light JacketEven on warm days, the vessel's interior can feel cool due to ocean breezes and air conditioning.

Watch for Wildlife ActivityKeep your eyes peeled near kelp beds where marine life is most active; guides will point out key spots.

Manage Motion SensitivityIf prone to seasickness, consider taking motion sickness medication before boarding as the vessel gently moves.

Recommended gear

Camera or Smartphone: Capture vivid underwater scenes through the vessel’s large viewing windows.
Sunglasses: Protect your eyes from strong sunlight when on deck before or after the tour.
Light Jacket: Stay comfortable in cool ocean breezes during the boat ride.
Reusable Water Bottle: Stay hydrated before or after your excursion.