A Kos glass bottom boat is a cruise boat with a clear window in its hull, so guests see the seabed and fish as they sail along the coast of Kos. Trips add swim stops and, on one boat, a mermaid show. Tours across the rest of the country are listed on Greece Tours.
The sections below cover the boats, what you see through the glass, the mermaid show, the Pserimos trip and the harbours. They also cover swim stops, who it suits, durations, the season and booking, with links into the Kos pages. The cruises shown are checked on GetYourGuide and Viator.
What is a Kos glass bottom boat cruise?
A Kos glass bottom boat cruise is a short sea trip on a boat with a glass floor. The glass sits in the hull, the part of the boat under the water. You watch fish, the seabed and a shipwreck, then swim.
The glass works like a diving mask. Ripples on the surface no longer blur the view. Passengers see the underwater world and stay completely dry the whole time.
On a Kos glass bottom boat you ride on the open upper deck first. When the boat stops over a site, you go below to the glass. Kos Town trips last 90 minutes or 2.5 hours, far shorter than a full-day pirate cruise from Kos.
Which Kos glass bottom boat cruises can you book?
Four online listings cover two Kos glass bottom boat operators in Kos Town. The Yellow Submarine runs a 90-minute trip with a mermaid show. The Dorry speedboat runs a 2.5-hour trip to Pserimos. Kefalos has its own glass-bottom tours.
- Kos Town: Glass-Bottom Boat Cruise with Swimming Stops: Dorry, 2.5 hours, Kos Town harbour.
- Dory’s Glass Bottom Boat Adventure in Pserimos and Pserimos Beach: Dorry, 2.5 hours, Kos Town harbour.
- Kos: The Yellow Submarine 1:30-hour cruise: mermaid show, 90 minutes, Kos Town harbour.
- 90 Minutes Glass Bottom Boat with Mermaid Show: Yellow Submarine, 90 minutes, Kos Town harbour.
- Gulf of Kefalos Glass Bottom Boat Tour: 2 to 4 hours, Kamari harbour in Kefalos.
The Yellow Submarine once sailed under the name Sea Explorer. It is a 20-metre boat that carries up to 50 passengers. Despite its name, it never dives under the water.
Dorry, also spelled Dory, is named after the fish from Finding Nemo. This fast Kos glass bottom boat takes up to 70 guests. Its sister boat, Nemo, also sails to a wreck and a quiet bay near Pserimos.
What do you see through the glass on a Kos glass bottom boat?
Through the glass of a Kos glass bottom boat, you see shoals of fish and the sandy seabed. The boats also hold still above an old shipwreck. On the Yellow Submarine, a diver swims right beneath the windows.
The Dorry stops right above an old cargo ship near Pserimos. It reaches the wreck after about 35 minutes of sailing. The crew talks about the ship while you look down.
The Yellow Submarine visits a wreck close to the Kos Town coast. Its diver holds shells and fish food against the glass. This brings the fish in close for photos.
In the Gulf of Kefalos, a Kos glass bottom boat passes Paradise Beach. There, streams of bubbles rise from the seabed into the water. Guests on that tour also stop at Camel Beach, a small cove between rocks.
What is the mermaid show on the Yellow Submarine Kos glass bottom boat?
The mermaid show on the Yellow Submarine Kos glass bottom boat is a live underwater act. A performer in a mermaid tail swims past the windows. A certified diver joins her below the hull during the stop.
The show starts once the boat stops and guests move down to the glass deck. The mermaid swims past the windows twice. Then the diver appears in front of the glass.
The crew calls it simply the show and keeps the mermaid a secret. Parents use this to surprise their children. After the act, guests take photos with the diver.
The Kos glass bottom boat then moves to a swim spot near the coast. Guests jump from the boat, swim and snorkel before the ride back to the harbour.
What does the Pserimos trip on a Kos glass bottom boat include?
The Pserimos trip on a Kos glass bottom boat includes a wreck viewing and a long swim stop. The Dorry covers the whole route in 2.5 hours. About 80 minutes of that time is at the island.
Pserimos is a small island about 2 nautical miles from Kos, between Kos and Kalymnos. Only 84 people lived there at the last census. Its main beach, Avlakia, has golden sand.
- A swim stop at a bay that crews call the Blue Lagoon, 5 minutes from the wreck.
- About 80 minutes at Pserimos for swimming and snorkelling.
- Jumps of about 4 metres from the top deck, plus a slide.
- Bread to feed the shoals of fish beside the boat.
The Dorry has two decks. The lower deck is shaded and holds the glass, while the top deck is open to the sun. Drinks, cocktails and snacks are on sale on board.
This Kos glass bottom boat trip gives you one swim stop at Pserimos. For a full day in the island’s harbour village, take a Pserimos day trip from Kos.
Where does a Kos glass bottom boat leave from?
Every Kos glass bottom boat in Kos Town leaves from the main harbour in the centre. The waterfront street there is called Akti Kountouriotou. Boats on the southwest coast leave from Kamari, the port of Kefalos, for Kefalos Bay.
- Kos Town harbour, Dolphins Square: Dorry and Nemo, with check-in 20 minutes before sailing.
- Kos Town harbour, near the I Love Kos sign: the Yellow Submarine.
- Kamari in Kefalos: glass-bottom tours to Kastri island, Camel Beach and Paradise Beach.
- Kardamena, about 30 km from Kos Town: a port for day boats to Nisyros.
Kos Town harbour lies below the Castle of Kos. Each Kos glass bottom boat passes the castle walls on the way out. See Kos Town for the harbour and old streets.
Kefalos village stands on a cliff above Kamari Bay and was once the island’s capital. The Kamari glass-bottom trips last about 3 hours. Guests visit the small church on Kastri island.
Which swimming and snorkelling stops does a Kos glass bottom boat make?
Every Kos glass bottom boat stops for a swim. The Yellow Submarine makes two stops: one near a shipwreck and one off a sandy coast. Dorry and Nemo sail to a secluded bay on Pserimos, the small island between Kos and Kalymnos.
On the Dory trip, the Kos glass bottom boat sails for about 35 minutes. It first stops over an old cargo shipwreck near Pserimos. The swim stop lies five minutes further on. Guests call this bay the Blue Lagoon.
The Pserimos stop on the Dory itinerary lasts about 80 minutes. Guests have time to swim ashore and rest on the sand. Longer snorkel trips are covered in the guide to snorkelling on Kos.
- Jumping into the sea from the top deck
- Snorkelling over the seabed with a mask
- Feeding bread to shoals of fish beside the hull
- Sliding into the water on the Dorry waterslide
Who suits a Kos glass bottom boat?
A Kos glass bottom boat suits families and non-swimmers. It also suits anyone who wants to see the seabed while staying dry. The Yellow Submarine was designed with family and child safety in mind. The Dory trip takes guests aged 0 to 99.
On a Kos glass bottom boat, non-swimmers watch fish from the glass deck below. On Dorry, infants sit on an adult’s lap. Pushchairs are allowed on board, and the crew lends float vests.
The Dory trip is not wheelchair accessible. The boarding ladder reaches only a short way into the water. Guests with weak arms or poor mobility find the climb back on board hard.
The Yellow Submarine cruises slowly, at about 11 to 14 km/h. Its short trip suits guests who feel seasick on long sailings. More family ideas sit in the guide to Kos with kids.
How long does a Kos glass bottom boat cruise last, and what is included?
A Kos glass bottom boat cruise lasts 90 minutes to 2.5 hours. The Yellow Submarine trip runs 90 to 100 minutes. Dorry and Nemo take 2.5 hours for the round trip to Pserimos. Every boat has a toilet on board.
Food and drinks cost extra on Dorry. A bar on board sells soft drinks, beer and crisps. Hotel pick-up is not part of the Dory trip.
- Two glass viewing areas on Dorry
- Two upper decks with roofs on Dorry
- Room for up to 70 guests on Dorry
- Room for up to 50 guests on the Yellow Submarine
- Snorkel kit in children’s sizes on the Yellow Submarine
A Kos glass bottom boat trip fits easily into a morning or an afternoon. By contrast, a three-island cruise from Kos Town takes six hours or more.
When does a Kos glass bottom boat run?
A Kos glass bottom boat runs daily through the boat season, from late April to October. The Yellow Submarine leaves Kos Old Harbour at 10:00, 14:00 and 16:00. Nemo leaves at 11:00 and returns at 13:30. Dorry also sails a 13:30 trip.
Departures peak from June to September. The 10:00 Kos glass bottom boat is cooler than the afternoon sailings. The afternoon trips leave in the hottest part of the day.
In high summer the meltemi blows across the Aegean. This is a strong, dry wind from the north. Rough water stirs up sand and makes the view through the glass less clear.
A glass-bottom sunset trip with Greek meze, small shared plates, lasts one to two hours. Evening sailings appear on the Kos sunset cruise page. Seasons are covered in the guide to when to visit Kos.
How do you book and cancel a Kos glass bottom boat cruise?
You book a Kos glass bottom boat cruise online through GetYourGuide or Viator. Tickets are also sold by the crew on the quay. The GetYourGuide and Viator listings allow free cancellation up to 24 hours before departure, with a full refund.
The Yellow Submarine listing offers reserve now, pay later. That means you hold a seat and pay closer to the date. The Dory ticket on Viator is a mobile ticket shown on your phone.
Dorry waits at the Kos dock next to Dolphins Square. The GetYourGuide meeting point is Akti Kountouriotou 44. Every trip ends back where it started.
A Kos glass bottom boat follows a fixed route and timetable. Groups wanting their own route hire a small motorboat instead. The guide to boat rental without a licence explains how it works.
Frequently Asked Questions
Are Dorry and Nemo the same Kos glass bottom boat?
They share one brand. The Dory Facebook page now runs under the name Nemo Glass Bottom Boat Kos. Reviewers even call it the Dory/Nemo boat. Both names come from the film Finding Nemo, and the decks carry its cartoon theme. Dory is the forgetful blue fish in that film.
Can you take photos with the Yellow Submarine diver?
Yes. The listing offers photos with its certified diver, a trained scuba professional. The crew also takes pictures of guests during the cruise. Back at the harbour, these pictures are turned into fridge magnets to take home. Pack a waterproof phone case if you plan to film while swimming.
Which languages does the crew speak?
The Dorry trip on GetYourGuide lists commentary in English, Greek, Italian and German. Its Viator version covers six languages, including Dutch. The audio guide works through a QR code, a square barcode you scan with your phone. No headphones are needed. The Yellow Submarine offers guided English plus one more language.
What do you pack for a Kos glass bottom boat trip?
Wear swimwear under your clothes and bring a towel. One Yellow Submarine guest advises taking swimming gear to get full value from the trip. A Dorry guest suggests bringing your own snorkel mask. Sun cream and a hat help on deck. Keep bags small, as the glass deck below is a tight space.