Rhodes Town: Submarine Cruise with Underwater Views

The best part of this Rhodes cruise happens just below your feet, where a diver feeds a swirl of colorful fish beside the submarine’s large viewing windows. You also get a pleasant run around Mandraki Harbor, the Old Town walls, Elli Beach, and the former site of the Colossus of Rhodes.

I like the short 45-minute format, which fits neatly between sightseeing stops, and the fact that you can switch between the air-conditioned underwater cabin and the open deck. The $23 price also makes sense for families, especially when the fish-feeding show grabs children’s attention.

The main drawback is space. The lower cabin can feel crowded when everyone heads downstairs, and the commentary may be hard to hear. The 18:30 departure does not include the diver show, so check the time before booking.

Key points

• The underwater observatory sits 2.5 meters below the surface, while the vessel itself remains above sea level.
• A diver feeds hundreds of fish directly outside the viewing windows during the main underwater portion.
• Mandraki Harbor provides the departure point, opposite the Bank of Greece building at Pl. Eleftherias.
• You see Rhodes from two angles, with underwater windows below and open-air views from the deck.
• The cruise passes major sights, including the Old Town walls, Elli Beach, the Tourist Harbor, and the former Colossus site.
• The 18:30 cruise skips the fish-feeding show, an important detail for families booking around sunset.

What the Poseidon Submarine really is

Despite its name, this is not a voyage in a fully submerged vessel. Poseidon Submarine stays on the surface, with an underwater viewing hull extending 2.5 meters below the waterline. That setup gives you a stable, easy way to see the seabed without swimming, snorkeling, or wearing special equipment.

The lower cabin has large windows and air conditioning. You sit indoors and look out at the Aegean water, rocks, sea grass, and fish. If the cabin becomes too warm or crowded, you can go upstairs to the deck for the breeze and views of Rhodes.

I think that distinction matters when you decide what to expect. This is a gentle harbor cruise with an underwater viewing area, not a serious marine expedition. You will not be exploring deep water or a wide range of habitats, but you can get a close look at fish gathering around the diver.

Starting at Mandraki Harbor

The meeting point is Poseidon Submarine at Mandraki port, opposite the Bank of Greece building at Pl. Eleftherias. Mandraki sits in the center of Rhodes Town, so the cruise is easy to pair with a walk through the medieval city or a visit to the harborfront.

The harbor itself is part of the experience. This is the port associated with the traditional location of the Colossus of Rhodes, one of the ancient world’s famous wonders. The statue no longer exists, of course, but seeing the harbor from the water gives you a useful sense of the entrance and its position beside the modern city.

Allow enough time to locate the boat. The dock area is central, but Mandraki has several waterfront attractions and boats. Your ticket identifies the Poseidon Submarine meeting point, and the departure is close to the Bank of Greece landmark.

Ten minutes around Mandraki Harbor

The opening part of the cruise takes about ten minutes. From the water, Rhodes Town looks less like a collection of separate sights and more like one compact waterfront city. You can see the harbor, the shoreline, and the old fortifications from an angle that is difficult to get on foot.

This is also your chance to settle in and decide where you want to spend the underwater section. If you prefer fresh air and broad photographs, the deck is the better place. If your main goal is the marine life, head below when the crew announces the viewing portion.

The crew provides information in English, with an audio guide also available in English and German. The historical material covers sights such as the harbor, the Knights, the city walls, and the former Colossus site. Audio volume has been a weak point at times, particularly when music is playing, so do not count on hearing every sentence clearly from every seat.

Passing the Palace and the Old Town walls

The route continues past the area of the Palace of the Grand Master of the Knights of Rhodes and the Old Town. You will not go inside the palace or tour the medieval streets during this cruise. Instead, you get a water-level view of the stone walls and the historic waterfront.

That view is especially useful early in your time in Rhodes. The Old Town can feel enclosed when you walk inside it, with narrow lanes and high walls. From the sea, you can see the scale of the fortifications and understand how the harbor relates to the defensive city.

The cruise also passes by the Tourist Harbor and the area around Elli Beach. These sections are scenic rather than deeply informative, but they break up the history commentary with open views of the coast. Bring your camera, though glare on the windows and bright sunlight can affect photographs.

The underwater show and the fish-feeding session

The main event lasts about twenty minutes. You can sit in the lower cabin and look through the wide windows as the crew positions the vessel for marine-life viewing. The diver then enters the water and feeds the fish near the glass.

This is where the cruise works best for children. The diver’s movements give everyone something specific to watch, while the fish gather in a visible group. Several families have found the show more engaging than simply looking through a glass panel at empty water.

You might see sea grass, rocks, and schools of fish in the area outside the windows. The number and clarity of fish can change with water conditions. On some departures, the water has been clear enough for excellent viewing. On others, cloudier water or dirty glass has made the details harder to see.

Do not expect a full catalog of Aegean marine life. The viewing area may show mostly one type of fish in one habitat, which disappointed children hoping for many species or larger animals. There are no claims of sharks, whales, or a large reef environment. The appeal is the simple spectacle of fish gathering close to the diver.

The crew’s underwater performance adds a playful touch. Past departures have included underwater photos and, in some cases, footage shared through the operator’s Facebook page. Treat that as a possible extra rather than a promised part of the package.

Choosing between the cabin and the deck

The cruise gives you two distinct experiences, and you should use both. The lower observatory offers the best chance to see the fish, while the upper deck gives you sea air and a clearer view of Rhodes.

The cabin is air-conditioned, but it can still feel close when the whole boat heads downstairs. Some people have found it uncomfortable after five or ten minutes, particularly during hot summer weather. Seating can also become an issue when people save several places or spread out.

If you are traveling with one child, arrive ready to move when the underwater portion begins. The crew has helped reorganize seating when the lower deck became cramped, but it is still sensible to avoid waiting until the last moment. Families may prefer to split their time, with one adult taking photographs from the cabin while another enjoys the deck.

The windows are the key feature, so clean glass matters. Conditions have varied. When the windows are clear, the underwater view is rewarding. If they are smudged or the sea is cloudy, the show loses some of its impact.

Is $23 a fair price?

At $23 per person, this is one of the easier Rhodes activities to justify if you want a short outing rather than a full-day boat trip. You get a cruise, sightseeing from the harbor, the underwater observatory, the fish-feeding session on eligible departures, an English and German audio guide, and access to the onboard bar.

The price works particularly well for families. A long sailing excursion can cost much more and take up half a day. This cruise gives children a clear central event and still leaves you time to explore the Old Town, visit the Palace of the Grand Master, or sit at Elli Beach.

It is also useful as a filler activity. If you have a spare hour before dinner, a ferry, or another booking, the 45-minute duration keeps your day flexible. The cruise is short enough for a child who loses interest on long boat trips, and several people have found it enjoyable as a simple break from walking.

The value is less certain if you want serious wildlife viewing. The underwater habitat is limited, the commentary may be difficult to hear, and the boat can feel crowded. For a dedicated marine-life experience, snorkeling or a longer boat trip may offer more variety. For a low-cost look at the harbor with a fun fish show, the price is strong.

Timing, weather, and the 18:30 warning

Check the departure time carefully. The 18:30 cruise does not include the diving show, so do not choose it if the underwater fish-feeding session is your main reason for going.

Sunlight can affect the underwater view. Bright conditions have produced enjoyable cruises and good scenery, but glare on the windows may make photographs tricky. Cloudy water can also reduce visibility. The deck remains worthwhile even when the fish are difficult to see because you still have the harbor and Old Town views.

The supplied information confirms free cancellation up to 24 hours before departure, with a full refund, and a reserve-now, pay-later option is available. Starting times depend on availability. The boat is wheelchair accessible, which makes this a more practical choice than many water activities, though the most comfortable seating position for each passenger is best checked with the crew at the port.

Who will enjoy this cruise most?

I would put this near the top of the list for families with children. The diver, the fish, and the change between deck and cabin keep the activity varied. Children do not need to swim, and adults get a quick look at Rhodes from the water.

It also suits couples and solo visitors who want a relaxed harbor trip without committing to a full sailing day. The mix of local history, coastal views, and marine life gives you more variety than a simple harbor loop.

It is less suitable if you dislike enclosed spaces or expect a quiet, polished sightseeing cruise. The lower cabin can become busy, and the audio may not carry well. If you are sensitive to heat, plan to spend part of the ride on deck.

You should also temper expectations if you have already taken a better-known underwater tour elsewhere. Rhodes offers a modest harbor habitat rather than a large marine park. The experience is about access and convenience: you can sit comfortably, watch a diver feed fish, and return to the center of town in under an hour.

Practical tips for a better ride

• Confirm the departure time if you want the fish-feeding show. Avoid 18:30 for that purpose.
• Arrive with your meeting point clear: Poseidon Submarine at Mandraki port, opposite the Bank of Greece.
• Keep your camera ready for the diver and the Old Town walls, but expect glare through the glass.
• Use the deck and the lower cabin rather than staying in one place for the whole cruise.
• If you want a lower-deck seat, go down promptly when the underwater viewing begins.
• Do not rely fully on the commentary. Sit near the audio source if you want the best chance of hearing the history.
• Bring a little extra money if you want a drink from the onboard bar, since drinks and personal expenses are not included.

Should you book the Poseidon Submarine?

Book it if you want a cheap, short, family-friendly look at Rhodes from the water. The fish-feeding show is the reason to choose it, and the views of Mandraki Harbor and the Old Town add real value to the 45 minutes.

Skip it if you want a wide range of marine species, a long open-water cruise, or a polished historical tour with consistently clear narration. For most people, though, the modest price, central location, and easy format make this a sensible addition to a Rhodes Town day. Just choose a departure with the underwater show and be prepared for a crowded cabin.

FAQ

Where does the Rhodes submarine cruise leave from?

It leaves from Mandraki port at Poseidon Submarine, opposite the building of the Bank of Greece at Pl. Eleftherias 85100.

How long is the cruise?

The cruise lasts 45 minutes. The route includes time around Mandraki Harbor, the Palace of the Grand Master area, the Old Town, and marine-life viewing.

Does the boat go fully underwater?

No. The vessel remains above sea level. Its underwater observatory hull sits 2.5 meters below the surface.

Can I see a diver feeding fish?

Yes, the cruise includes a diver feeding fish near the underwater viewing windows, except on the 18:30 departure.

What languages are available?

A live tour guide is available in English, and an audio guide is offered in English and German.

Is the cruise wheelchair accessible?

Yes, the activity is listed as wheelchair accessible.