A Kos glass bottom boat trip is a sea cruise on a boat with viewing windows in the hull. You watch fish and the sea floor through the glass. Below you find the boats, the route, the swim stops and the booking rules. The homepage lists more Greece Tours like this one.
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What is a Kos glass bottom boat trip?
A Kos glass bottom boat trip is a short sea cruise on a boat with a glass floor. You stay dry while fish and an old shipwreck pass below. The harbour boat runs about 90 minutes and the speedboat two and a half hours.
One Kos glass bottom boat trip is a harbour cruise of about 90 minutes. Another is a speedboat cruise of two and a half hours. Both start at the harbour of Kos town. Each one puts a glass view of the water under your feet.
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The harbour boat has a special glass area underneath, so you look straight down at the water. It carries life vests and a toilet, and a bar on board sells drinks. A live host leads the trip in English. The cruise is built for travellers who want sea activities without spending half a day on the water.
On the speedboat, a Kos glass bottom boat cruise spreads over two decks. The top deck is open to the sun. You choose a sunny spot on the sundeck or a seat in the shade. The boat has a thick glass floor and two glass-bottom viewing areas. A toilet is on board.
On a Kos glass bottom boat harbour cruise, marine life, rocks and a shipwreck drift by underneath. On the speedboat, the glass shows fish, sea creatures and an old shipwreck. Passengers walk to the glass-bottom sections to look down. Children can entertain themselves by spotting different creatures.
Passengers on the speedboat watch the fish through the glass from the shaded area, drink in hand. The crew tells everyone when to gather around the thick glass bottom. The main drawback on the speedboat is glass clarity, which can vary. Passengers can find the panels a little fogged or scratched.
The crew handles the talk and the safety. The speedboat host speaks English, Greek, Italian and German and gives a short marine life introduction. A welcome overview and a safety briefing open the trip. An audio commentary plays through the speakers in English and Greek.
The harbour cruise suits families with kids in particular, and it appeals to a broad audience beyond them. A Kos glass bottom boat of this kind offers family-friendly entertainment in 90 minutes. The toilet on board helps families with young children, and the short length keeps the outing easy.
The speedboat cruise is described as great for families and beginners. It also suits couples and solo travellers who want a relaxing half day. Children enjoy spotting fish. The crew pays attention to children and to less confident swimmers. The format is right for anyone who wants a quick ocean activity.
A Kos glass bottom boat sailing is yours to pick on the speedboat. The cruise runs in the morning, at noon and in the afternoon, and it lasts two and a half hours. Drinks come from the bar on board and are not in the ticket. On the harbour cruise, snacks, soda and alcohol are left out too.
Where does a Kos glass bottom boat sail?
A Kos glass bottom boat sails from the harbour of Kos town. The speedboat trip passes the castle and sails on to Pserimos for a swim. The harbour cruise with the mermaid show stops at a wreck and at a swim spot.
The speedboat and the mermaid-show cruise both start in the harbour of Kos town. The speedboat waits at the dock next to the Dolphins square. The other boat boards near the “I love Kos” sign. Public transport is available close to both boarding points. Transfers are an extra on the mermaid cruise.
A Kos glass bottom boat of the speedboat type leaves its dock and sails along the coast of Kos. The trip opens with a look at the harbour from sea level. Passengers see the castle and the old town from the water. The boat then heads for Pserimos and returns along the eastern coast of Kos.

Pserimos lies between Kalymnos and Kos, close to the Turkish coast. On the speedboat trip, passengers visit a beach on the island and swim in the sea there. The same trip then brings them back to the harbour where it began.
A recorded commentary plays through the speakers of the speedboat while it sails. Music and entertainment are part of the ride. The boat has two decks, one open to the sun and one in the shade. A bar on board sells drinks to the passengers.
The speedboat version of a Kos glass bottom boat also passes an old shipwreck. Passengers gather around the thick glass bottom and look down at the wreck. The boat makes a short stop there so that passengers can look at it through the glass.
The Kos glass bottom boat cruise with the mermaid show follows its own route from the harbour. One stop is by a shipwreck, and the glass in the hull shows the wreck drifting by below. The other stop is for swimming.
The swim stop of the harbour cruise lies near Kos Marina. Passengers swim, snorkel or jump from the boat into the water. The boat carries life vests for the swimmers. The cruise boat has a toilet and a bar on board.
The Kos glass bottom boat with the mermaid show adds live entertainment to the route. A mermaid and a diver appear during the trip and perform for the guests. They also take photos with the passengers.
The sea around Kos has a volcanic seabed with underwater caves and reefs. Divers at Therma beach find shoals of sea bream and colourful local wrasse. They also meet scorpionfish, octopuses, crabs and sea urchins. A Kos glass bottom boat shows whatever swims near the hull. The harbour cruise gives no promise of a sighting.
Which season and rules shape a Kos glass bottom boat trip?
A Kos glass bottom boat trip starts in late spring, and the speedboat’s afternoon sailings run to October. Poor weather can cancel a sailing. Age and health rules change from boat to boat, and a full refund needs a cancellation a day ahead.
The harbour boat reaches Kos at the end of April, and its official cruises start in late spring. From the old harbour it lists daily sailings at morning, noon, late noon, evening and sunset. Each of those is a Kos glass bottom boat departure.
The glass-bottom speedboat trip to Pserimos lists afternoon sailings from late spring to October. The June sailing runs from 18:00 to 20:30, and the October sailing runs from 16:15 to 18:45. Both last two and a half hours, so October simply starts earlier.
Heat peaks in July and August on a Kos glass bottom boat day. A weather-station table for Kos gives July a mean daily high of 30.4 degrees Celsius. August reaches 31 degrees, and neither month shows rain. On the speedboat the glass sits on the shaded deck, out of the sun.
The Aegean is low in nutrients and has little plankton, and that keeps its water clear. A crew still cannot promise a particular fish, because sightings cannot be guaranteed on the 90-minute harbour cruise.
Weather can end a sailing. The speedboat trip to Pserimos needs good weather. A cancelled sailing is moved to another date or refunded in full. The Aegean’s north wind, the meltemi, is at its strongest in the afternoon. Check the forecast before a Kos glass bottom boat trip.
Age rules for a Kos glass bottom boat depend on the boat. The harbour boat sells child tickets for ages four to 12, and infants travel free. On the speedboat trip, infants must sit on an adult’s lap. Ask the seller first if your child is younger than four.
The sunset cruise in the submarine-style boat is not suitable for wheelchairs. It is also not suitable for guests with travel sickness or claustrophobia. The 90-minute harbour cruise and the speedboat trip are both listed as suitable for all fitness levels. Pets are not allowed on the speedboat.
Pack swimwear, a towel, sun protection and sunglasses. Food is not included on the 90-minute harbour cruise, although the boat has a bar. Secure your valuables before you swim. The speedboat trip asks for a passport or ID for the whole trip.
Book a Kos glass bottom boat trip ahead in peak season. Booking pages show live availability by date, and the 90-minute harbour cruise can be reserved now and paid for later. A desk in front of the boat at the old harbour sells last-minute tickets. Meet at the dock 20 minutes before the speedboat leaves.
A cancellation a day ahead earns a full refund on the harbour cruise. The speedboat trip and the Gulf of Kefalos cruise follow the same rule. A later cancellation is not refunded on the harbour cruise or the speedboat trip. Changes inside the last day are not accepted there.