A Window Into the Reef Without Getting Wet
The glass-bottom boat ride at North Bay Island is the most accessible underwater experience anywhere in the Andaman Islands, and the perfect activity for travellers who want to see the reef without learning to swim, snorkel or scuba dive. The boat is a small fibreglass craft fitted with a large transparent panel built into the floor of the central cabin, through which passengers can watch the seabed, coral formations and marine life passing directly beneath their feet. The activity is short, inexpensive and family-friendly, and it serves as an excellent introduction to what the underwater Andaman world looks like for visitors who plan to do more in-water activities later in their trip.
The North Bay Reef
The reef at North Bay Island is one of the most accessible healthy coral systems in the Andamans. The reef extends in a narrow band along the northern shore of the island, with depths ranging from 2 metres in the shallows to 8 to 12 metres at the reef edge. The coral cover includes branching corals, table corals, brain corals, plate corals and the smaller bommies that host the most active fish populations. The reef has held up surprisingly well despite the volume of glass-bottom boat traffic, in large part because the boats follow established channels that minimise propeller damage to the coral. Underwater visibility ranges from 8 to 25 metres depending on tide, recent weather and time of day.
What the Glass Reveals
Looking down through the glass panel of the boat, passengers can typically observe a continuous sequence of underwater scenes. Schools of parrotfish in iridescent rainbow colours pecking at the coral surface, butterflyfish in mating pairs gliding between the bommies, the orange-and-white anemonefish (Finding Nemo's clownfish) guarding their host anemones, sea cucumbers moving slowly along the sandy patches, the occasional sea turtle (lucky sighting) feeding on sea grass, and the brightly coloured wrasses, surgeonfish and damselfish that make up the bulk of reef fish populations. The boat operator typically calls out species as they appear, helping passengers identify what they are watching.
The Iconic ₹20 Note Lighthouse
North Bay Island is famous beyond the diving community because of its appearance on the reverse side of the Indian ₹20 note. The lighthouse that features on the note is the same lighthouse that still operates on the island today — a small white-and-red structure on the eastern point of the island, originally built in 1858 by the British colonial administration. Visitors who land on the island after the glass-bottom boat ride can walk up to the lighthouse for a brief photo stop; the contrast between the famous ₹20 note image and the actual structure in person is one of the small but memorable highlights of the visit. The lighthouse is still active and operates as part of the modern Andaman navigation system.
Boat Types and Trip Length
Two types of glass-bottom boats operate from the North Bay jetty. The smaller boats accommodate 6 to 10 passengers and offer a more intimate experience with closer attention from the operator (₹500 to ₹1,000 per person for a 20 to 30 minute ride). The larger boats accommodate 15 to 25 passengers and offer a slightly less personal experience at lower cost (₹400 to ₹700 per person for the same duration). Both types follow similar routes through the reef channels, and both provide approximately the same range of underwater sightings. The smaller boats are slightly preferred by serious wildlife enthusiasts; the larger boats are better suited to families with small children who appreciate the additional space.
Sea Conditions and Tides
Water clarity at North Bay varies significantly with tide timing, recent weather and the time of day. The clearest conditions typically occur during the rising tide in the late morning, when the incoming clean ocean water has displaced the slightly turbid lagoon water and the sun is high enough to penetrate to the seabed. The murkiest conditions occur during the falling tide in the late afternoon, when accumulated debris from the day's boat traffic and shoreline activity reduces visibility. Sea conditions can also turn choppy by mid-afternoon, particularly during the monsoon shoulder months. Plan glass-bottom boat trips for the late morning slot (10:30 AM to 12 noon) for the best combination of water clarity and gentle sea conditions.
Reaching the Aberdeen Jetty
North Bay Island is reached by short ferry or speedboat ride from the Aberdeen Jetty in Port Blair, the capital of the Andaman Islands. The crossing takes 20 to 30 minutes depending on boat type and sea conditions. Ferries operate from approximately 8 AM to 4 PM daily during the open season (October to May), with departures every 30 to 60 minutes during the busy hours. Boat tickets can be purchased at the jetty (₹250 to ₹500 per person for the round-trip ferry) or as part of bundled island tour packages from Port Blair tour operators (₹800 to ₹1,500 per person for the ferry, the glass-bottom boat ride and access to the lighthouse). The Aberdeen Jetty is within easy auto-rickshaw distance of all Port Blair hotels.
Combining With Snorkelling and Beaches
The natural extension of a glass-bottom boat ride is a snorkelling session at the same North Bay reef, which lets you experience the underwater environment directly rather than through the glass. Most tour packages include the option to add snorkelling at an additional ₹500 to ₹1,000 per person, with gear and a guide provided. The small beach at North Bay is also worth a brief swim; the water here is calm, shallow and warmer than the open ocean. Many travellers combine the North Bay visit with stops at the nearby Ross Island (the former British administrative headquarters with atmospheric colonial ruins) and Smith Island into a single full-day Port Blair excursion. The combined trip is usually the most efficient use of a single day in the Andaman capital region.
Practical Notes for the Visit
Water clarity depends heavily on tide timing, so try to book the boat ride for the late morning slot when visibility is at its best. Seating near the glass panel fills quickly, particularly on the smaller boats; arrive at the jetty at least 30 minutes before departure to secure the best viewing position. Sunglasses may need to be removed during the actual viewing to reduce glare from the cabin lighting; bring a small cloth to clean them if you do. The boat ride is short (15 to 25 minutes of actual viewing time), so manage expectations — this is a quick introduction rather than a long excursion. Combine it with snorkelling at the same site for a fuller experience. Sea conditions can turn slightly choppy by afternoon during the open season, particularly in the shoulder months between October and December. The activity is generally safe and suitable for all age groups, including young children and elderly passengers; life jackets are provided on all boats and worn during the crossing.