Rhodes turns upside down in a submarine. This short Poseidon Submarine cruise gives you air-conditioned comfort below the surface, plus harbor views of Rhodes from Mandraki out toward the Old Town. Then the diver brings the sea life right to your windows.

I like two things a lot. First, the 360° panoramic views from inside the underwater cabin make it feel like you are watching a live aquarium. Second, the highlight is the diver feeding the fish, which brings plenty of multi-colored visitors close enough to enjoy without getting wet.

One drawback to plan for: the lower deck can get busy. On busier departures, it may feel cramped, and some seating areas can get sticky and hot, so you will want to manage where you sit.

Key highlights to know before you go

• Mandraki Harbour loop in 45 minutes, timed so you get a quick history-and-scenery sweep before the underwater viewing
• Huge windows inside an air-conditioned cabin, with the hull’s observatory sitting 2.5 meters below the surface
• Diver feeding right by your window, which is the best moment for clear fish spotting and photos
• Rhodes sights from the water, including the Mandraki area, Elli Beach, and the Old Town walls
• Onboard bar access and English-language guidance, with narration in English and German

Why this Rhodes submarine feels different from a normal boat ride

A regular boat tour shows you Rhodes from the waterline. This one takes you lower, without asking you to swim or snorkel. The submarine stays above sea level the whole time, and the underwater observatory is positioned about 2.5 meters down. That setup matters because it keeps the ride stable and comfortable while still letting you look out on the sea floor and fish.

The best part is the feeling of proximity. Instead of looking at specks in the distance, you watch fish come into a feeding zone right outside the big windows. When the diver enters the water and starts feeding, the action is close enough that even kids usually stop fidgeting and start pointing.

You also get a split experience that works for different moods. One moment you are watching Rhodes’ harbor and fortifications glide by. The next moment you are staring at fish and underwater surroundings like you dropped into a different part of the island.

Getting to Poseidon Submarine at Mandraki Harbour

Meet at Mandraki port at Poseidon Submarine, opposite the Bank of Greece. It is in the center of Rhodes, so it is convenient if you are already exploring Old Town or walking the seafront.

The activity is wheelchair accessible, and there is a live tour guide speaking English onboard. In addition, you get an audio guide in English and German. That combination is useful because it gives you a steady flow of information even if you miss part of the live narration.

There is also a bar onboard, and access is included. Drinks are not included, but at least you have the option to grab something while you wait through boarding or relax between the scenic cruising and underwater time.

Finally, plan to arrive with your camera ready. The feeding moment is the time to shoot. If you want the cleanest, most vivid shots, pick a window area that feels clear and avoid sitting right where people constantly block the glass.

The harbour cruise: Mandraki, Knights’ Palace area, and Old Town walls

The trip starts with a short hop along the Rhodes waterfront. You begin in the Mandraki Harbour area and then cruise past major sights. Along the way, you get a water-level look at the places you normally see from streets or viewpoints.

You will pass the area connected to the Palace of the Grand Master of the Knights of Rhodes. Even if you do not go inside, seeing the coastline from the sea helps you understand how Rhodes Town is laid out around the harbor. You also continue toward the Old Town, with a brief stretch that focuses on the waterfront and the walls.

From the water, you also get views linked to famous Rhodes history, including the spot where the Colossos of Rhodes once stood. That is not the monument itself, but it is a useful way to anchor the island’s story in a visible place.

Expect a mix of quick scenic segments and calmer cruising. This is exactly why the timing works. You get enough time to enjoy the harbor views, but you are not stuck on the boat for hours before the underwater part begins.

360° underwater cabin, air-conditioning, and the 2.5-meter observatory

What makes this submarine cruise feel special is how it turns underwater viewing into an indoor, low-effort activity. You are seated inside an air-conditioned cabin below the surface, and the windows are set to give a wide, 360° feel.

That design is practical. You can watch fish without balancing, without saltwater on your face, and without worrying about fin kicks. If you are traveling with kids, it reduces the usual “will we make it through the long ride?” stress.

The vessel stays above water at all times, while the underwater observatory is 2.5 meters below. So you are not “sinking.” You are simply looking out into the water from a protected viewing space, which also helps with motion sickness for people who usually avoid boats.

One more tip from real-world experience: visibility can vary. Some departures have clearer water and better window views, while others can feel harder to see through. If the water looks slightly cloudy when you board, keep your expectations flexible and focus on the moment when the diver feeds the fish, because that draws activity close to your windows.

The diver feeding the fish: what you’ll likely see and when

The fish feeding is the moment most people remember. The diver enters the water and begins feeding hundreds of multi-colored fish right in front of your window. That is not just entertainment. It changes how you experience the underwater scene.

Feeding creates a predictable viewing zone. Instead of scanning aimlessly for small movement, you can watch a concentrated area where fish gather. That makes it much easier for children and for anyone who feels new to marine life viewing.

You also get a chance to see underwater surroundings along with fish. Some spots can show sea grass and rocky areas, which adds texture to what you see. And occasionally, the crew may spot extra surprises like an octopus, which can add a fun, unexpected twist to the underwater viewing.

How much variety you will see depends on conditions and what the diver brings the fish to. One limitation to be aware of is that the underwater experience can feel more focused on a single habitat pattern than on a wide mix of species. If your goal is sharks, whales, or a huge variety of creatures, this is probably not the right match.

Also, note that the 18:30 cruise does not include the extra underwater show. You still get the submarine experience and underwater viewing, but that later departure has a smaller underwater program.

Deck views and ocean breeze time

Not everything happens below. You also have the option to relax in the cabin or walk out onto the deck for views from the water. That deck time matters because it gives you a break from the enclosed viewing space and helps you reconnect with the island scenery.

From the deck, you typically get clearer, brighter views of Rhodes’ coastline. You can enjoy the sea breeze and keep spotting landmarks as the boat passes the harbor edges and waterfront buildings.

This is also where you can reset if the underwater cabin gets busy. If you see people crowding around a particular viewing window, stepping out for a short moment can keep your comfort high and your attention fresh for the best fish-viewing window.

Audio, crew, and the practical onboard vibe

The tour uses audio narration plus a live English guide. The audio guide is available in English and German, which is helpful when you have mixed-language groups onboard.

That said, sound quality can vary. Some departures have had issues with the recorded commentary being hard to hear, especially if music is turned on. If you care about the history details, position yourself where the speakers are easier to hear, and do not rely on hearing everything perfectly from any seat.

The crew generally gets strong marks for friendliness and professionalism. They guide seating and keep the flow moving between scenic cruising and underwater viewing. On busier boats, there can be some crowding downstairs, and you may find you get moved around so space opens up. That kind of active help makes the difference between feeling stuck and feeling comfortable.

The onboard bar access is another practical touch. Even a small drink or snack can make the 45 minutes feel less like a rushed stop and more like a relaxed mini outing.

Price and value for money at about $23

At around $23 per person for a 45-minute experience, the value comes from the combination of three things: you get a short Rhodes waterfront cruise, you get underwater viewing without effort, and you get a diver feeding session timed for visibility.

It is not a long excursion. It is a compact experience designed for people who want an island activity that fits into a day of sightseeing. If you are exploring Rhodes Town on foot, this works because you do not lose your whole day to transport and long boat hours.

The strongest value signal is that people consistently say it feels like a “right-sized” outing. It is long enough for the harbor loop and the underwater highlight, but short enough that it usually does not derail your plans for Old Town.

If you are cost-sensitive, this is also a good choice because the included elements are meaningful. Submarine cruise is included, audio guidance is included, and bar access is included. Drinks are not included, but the core experience is already covered.

Who should book, and who should skip

This submarine cruise is best for families, first-time Rhodes visitors, and nature lovers who want an easy marine-life viewing option. Kids tend to love the fish feeding because the action is right there and the underwater scene stays stable and watchable.

Couples also tend to like it for a different reason. You get classic Rhodes Town scenery from the water and then a calm, unusual underwater window experience. It is a good “break” activity if you have already walked Old Town streets and want something lighter.

You might want to skip it if your main goal is a huge variety of marine animals or a long, hands-on underwater activity. This is focused viewing, not an all-day dive-style expedition. You should come for the fish feeding, the harbor sights, and the novelty of seeing Rhodes from below the surface.

And if you are sensitive to heat or crowding, have a plan. Sit strategically, and use the deck for resets if the lower cabin feels too warm or packed.

Should you book the Rhodes submarine cruise or not?

If you want a short, affordable activity that mixes Rhodes Town highlights with real underwater viewing, I think this is a smart yes. The best reason to book is the diver feeding session, because it turns underwater looking into something active and easy to enjoy.

I would hesitate only if you are expecting a big marine-species spectacle or you strongly rely on audio narration for every historical detail. If either of those is your top priority, you might feel slightly let down.

Otherwise, this is one of those practical Rhodes experiences where you walk away with photos, a new angle on the harbor, and a story that feels different from the usual sightseeing circuit.

FAQ

How long is the Poseidon Submarine cruise in Rhodes?

The duration is 45 minutes.

Where is the meeting point for the submarine?

You meet at Mandraki port at Poseidon Submarine, opposite the Bank of Greece.

What is included in the price?

Included: submarine cruise, audio guide in English and German, and access to a bar onboard.

Are drinks included?

No. Drinks are not included.

Is there a live guide onboard?

Yes. There is a live tour guide in English.

What languages are available for the audio guide?

The audio guide is available in English and German.

Does the submarine stay above the water?

The vessel remains above sea level at all times, while the underwater observatory is 2.5 meters below the surface.

Can I go outside on the deck?

Yes. You can leave the cabin and walk on the deck for views and the ocean breeze.

Is the 18:30 cruise different?

Yes. The 18:30 cruise does not include the extra underwater show.

Is it wheelchair accessible?

Yes, the activity is wheelchair accessible.