Cat Ba is the largest island in Ha Long's archipelago — and the only one where you actually live, eat, and sleep among locals. Three days is the sweet spot: enough time to kayak Lan Ha Bay, trek the National Park, and end with a night paddle through glowing plankton. This guide is what we tell our friends when they ask "what should I do in Cat Ba?" — written by guides who run these tours every week.
Day 1 — Arrive & ease in: Lan Ha Bay full-day cruise
Most travelers arrive Cat Ba mid-morning by ferry from Hai Phong or by bus-boat-bus from Hanoi. Drop your bags, grab a banh mi at the harbour, and join the Full-Day Lan Ha Bay tour the same day if you arrive before 8:30 AM — or take it Day 2 morning if you land later.
What you actually do
- Cai Beo floating village— one of the oldest fishing settlements in Vietnam, dating back 7,000 years. You'll cruise through wooden houseboats, see fish farms, and learn how families live their entire lives on water.
- Kayak hidden lagoons — Lan Ha has dozens of small lagoons reachable only through cave-mouths. The water is calmer and the limestone cliffs feel taller than Ha Long Bay because there are fewer crowds.
- Swim at Ba Trai Dao Beach — three small white-sand beaches connected at low tide. Bring water shoes; the sand has shell fragments.
- Vietnamese family-style lunch onboard— shared dishes: morning glory, grilled fish, rice, soup. Tell your guide if you're vegetarian — they'll plan ahead.
Cost & logistics
- Tour: 750,000 VND (~30 USD) per adult. Under-5 free, 50% off ages 5–10.
- Pick-up 8:00–8:30 AM from your accommodation. Return 5:00 PM.
- Bring: swimwear, towel (boat provides backup), reef-safe sunscreen, sunglasses, a light jacket for shaded boat sections.
Where to eat dinner
Walk down 1/4 Street to our food guide for current local picks. Most travelers go to Green Mango or Yummy for seafood — but the small-plate spots two blocks back from the harbour are where guides actually eat.
Day 2 — Trek into the wild: Cat Ba National Park & Viet Hai Village
Day 2 is the day most travelers skip and later regret. The National Park + Viet Hai trek is the only chance you have of seeing the critically endangered Cat Ba Langur — there are fewer than 70 left in the wild, all on this island.
The route
- Morning trek — start at the Park entrance, hike past the Frog Pond freshwater lake, climb Doc Dai mountain (medium-hard, plan for switchbacks).
- Lunch at Viet Hai Village — a 100-person village reachable only by boat or trail. Local family-cooked meal. Optional fish-massage (small fish nibble dead skin off your feet — strange but legitimate).
- Cycle the village — bicycles included. The village is 1.2 km end to end with rice paddies and a 200-year-old banyan tree.
- Boat back through Lan Ha Bay — different perspective from Day 1, with the late-afternoon light hitting the karsts.
Difficulty & what to wear
This is rated Medium-Hard— about 4 hours of walking with elevation. Wear closed shoes (sneakers OK, hiking shoes better), long socks against bug bites, and bring 1.5L water minimum. The Hai Quan (Navy) Peak add-on (+200k VND) extends the hike by 90 minutes and gives you a 360° panorama — only do it if you're fit.
Pro tip from our guides: ask to start at 7:30 AM instead of the standard 8:30 if you can. The langurs are most active in the first two hours of light. After 10 AM they retreat into the upper canopy.
Day 3 — The unreal: Sunset & Night Kayaking with bioluminescent plankton
Save this for last — it's the experience that makes Cat Ba feel unreal. The Sunset & Night Kayaking tour runs 4:00 PM to 9:30 PM and combines two distinct experiences: a sunset cruise, then a true after-dark paddle through water that lights up around your paddle blade.
What bioluminescent plankton actually is
Microscopic dinoflagellates that emit blue-green light when disturbed — drag your hand through the water and the trail glows for a half-second. It's strongest on moonless nights between April and October, in calm water with low boat traffic. Lan Ha Bay's protected coves are some of the best places in Southeast Asia to see it.
What the night looks like
- 4:00 PM — pickup from your accommodation
- 5:00 PM — sunset cruise through Cai Beo, swim stop in Lan Ha
- 7:00 PM — Vietnamese dinner onboard while the boat repositions to a quiet lagoon
- 8:00–9:00 PM — night kayaking. Headlamp on for launch, then off in the lagoon. Paddle slowly, splash gently — the plankton respond to motion.
- Optional: jump in. Swimming through bioluminescent water is the closest thing to swimming through stars you'll ever do.
- 9:30 PM — back to your accommodation
Cost & honesty
- Tour: 1,050,000 VND (~42 USD) per adult.
- Plankton intensity varies — we always tell guests it's weather-dependent. New moon nights are best. Bright moonlight washes out the glow.
- Group capped at 25 — book 1–2 days ahead in peak season.
If you have a 4th day: pick one
Most travelers stretch to four nights. Three good options depending on your style:
- Lazy luxury — D'Charme Lux Cruise (850k VND). Bigger boat, jacuzzi, sunset tea party. Good if you have older parents traveling.
- Self-explore — Easy-Rider or scooter (from 150k). Trung Trang Cave, Quan Y (Hospital Cave), and Cannon Fort all in one day at your own pace.
- Premium combo — Fullday + Night Combo (1.7M VND). 12-hour day combining everything from Day 1 and Day 3 into one — for travelers short on time.
Getting to Cat Ba
From Hanoi: limousine bus → speedboat at Got Harbour → bus to Cat Ba town. 4–5 hours total. ~350,000 VND each way.
From Hai Phong: hydrofoil from Ben Binh harbour directly to Cat Ba town. 1 hour. ~250,000 VND.
Full route detail and current schedules: our Transport guide.
Pre-arrival checklist
- Cash — some tour ad-ons and food spots are cash-only. ATMs in Cat Ba town accept Visa/Master.
- Power adapter — Vietnam uses Type A/C/D plugs (the flat 2-pin and round 2-pin are most common).
- SIM — Viettel or Mobifone tourist SIM at Hanoi/Hai Phong airport. Coverage on Cat Ba is solid in town and patchy on tours.
- Insurance — most tour insurance covers boat/trek but double-check kayaking and swimming coverage.
Booking the trip
We run all the tours mentioned above directly — no middlemen, no commission resellers. Browse all 9 experiencesor message us on WhatsApp if you want a custom 3-day package combining specific tours. We'll usually reply within 30 minutes during the day.
See you on the water. Or in the jungle. Or in the glowing dark.