Cat Ba is the largest island in the Ha Long – Lan Ha archipelago and, in our (admittedly biased) opinion, the best base in northern Vietnam for anyone who loves the outdoors. Almost half the island is protected as Cat Ba National Park, the bay starts a few minutes from town, and the evenings are all about fresh seafood by the harbour. Here are the ten experiences our team on the island recommends most, with practical tips for each.

Kayaks and a tour boat inside a limestone cave in Lan Ha Bay — Kayaking into hidden caves and lagoons is the highlight of any visit to Cat Ba.

1. Kayak through caves and lagoons in Lan Ha Bay

The number one reason to come. From Cat Ba it takes only minutes by boat to reach the karst islands of Lan Ha Bay. Paddle through low cave arches such as Dark & Bright Cave and Bat Cave into enclosed lagoons that big boats cannot enter – it is silent apart from birds and the splash of your paddle.

Tip: go on a full-day cruise rather than a quick 2-hour trip, so you have time to kayak and swim. Our Lan Ha Bay & Ha Long Bay day cruise (from US$27) includes kayaking, a beach stop and lunch.

2. Hike to Ngu Lam Peak in Cat Ba National Park

Cat Ba National Park, part of a UNESCO Biosphere Reserve, covers much of the island’s interior. The classic trail climbs stone steps through tropical forest to Ngu Lam Peak, where a viewpoint looks out over endless green hills. Fitter hikers continue towards Cao Vong Peak.

Hiker celebrating at the top of a forest viewpoint in Cat Ba National Park — The climb to Ngu Lam Peak is short but steep – and worth every step.

Tip: start early to avoid the midday heat, wear proper shoes and bring at least a litre of water. Join a guide on our trekking & Lan Ha Bay adventure or the tour from Ninh Binh.

Group of travellers trekking through the forest of Cat Ba National Park — Guided treks follow forest trails rich in birds, butterflies and old trees.

3. Walk through Trung Trang Cave

Close to the national park entrance, this limestone cave runs about 300 metres straight through a mountain, with stalactites and stalagmites lit along the path. It takes 20–30 minutes and is a cool escape on a hot day.

4. Visit Hospital Cave

Built into a mountain during the American War, this three-storey hidden hospital once treated soldiers and sheltered local leaders. The rooms, operating theatre and escape tunnels give a vivid picture of island life in wartime.

5. Cycle through Viet Hai village

Tucked inside the national park and reachable only by boat or on foot, Viet Hai is a tiny village of rice fields, fruit gardens and karst cliffs. Cycle or ride an electric car along the quiet lanes and try a natural fish foot massage. Our Viet Hai village & sunset tour (from US$28) includes bicycles and a sunset party on the way back.

6. See glowing plankton at night

On dark nights, roughly from April to October, bioluminescent plankton light up around your paddle and fingertips like tiny stars. It is one of the most magical things you can do in Vietnam.

Blue glowing bioluminescent plankton in the water at night in Lan Ha Bay — Bioluminescent plankton glow brightest on dark, moonless summer nights.

Tip: the glow is strongest far from lights and on nights with little moon, and it varies from night to night. Try our plankton kayaking tour.

7. Spend a night on the water

Sleeping in the bay gives you sunset, stars and sunrise without another boat in sight. Choose a luxury overnight cruise with a cabin, cooking class and squid fishing, or a lively floating house with kayaks and fishing rods on our 3-day floating house trip.

Aerial view of a floating house in the middle of Lan Ha Bay — A night in a floating house: fishing from the deck and kayaking at your door.

8. Explore the island by motorbike

Cat Ba’s roads are quiet and scenic, climbing over forested hills and along the coast. Several of our tours include a free motorbike so you can visit the national park, caves and beaches at your own pace.

Tip: you need a licence recognised in Vietnam (for example an International Driving Permit) and should be an experienced rider. Check that your travel insurance covers motorbikes.

9. Relax on Cat Co beaches and in the bay

Cat Co 1, 2 and 3 are small beaches a short walk from Cat Ba Town – perfect for a late-afternoon swim. For softer sand and clearer water, the beaches of Lan Ha Bay such as Ba Trai Dao are even better.

Swimmers in the clear water of a small beach in Lan Ha Bay — The small beaches of Lan Ha Bay are perfect for a swim between kayaking stops.

10. Eat fresh seafood on the waterfront

Clams steamed with lemongrass, grilled squid, fresh fish and shrimp from the floating farms – Cat Ba’s harbour restaurants serve it all at friendly prices. Many of our cruises also include a seafood lunch on board.

Travellers sharing a seafood meal together on Cat Ba — Seafood dinners are a highlight of any stay on Cat Ba.

Tip: seafood is often sold by weight – ask for the price per kilo before ordering.

How many days do you need on Cat Ba?

1 day: a full-day cruise with kayaking.
2 days: a cruise plus a trek or motorbike day – the most popular choice, as on our Lan Ha Bay & Cat Ba 2D1N tour.
3 days: add a night on the water and time to relax.

Getting there is easy – see how to get from Hanoi to Cat Ba and our bus tickets. For more ideas read the Cat Ba Island guide, or send us your dates for a free tailor-made plan.