What Cong To Vo actually is
Cong To Vo is a natural rock arch carved from volcanic basalt on the northeast shore of Ly Son Island, about 25 km off the coast of Quang Ngai province in central Vietnam (베트남 / 越南 / ベトナム). The arch formed over centuries as waves eroded the softer rock beneath a harder basalt cap, leaving a rough doorway that frames the sea. It sits maybe four meters tall — not massive, but striking in person because of the dark, porous volcanic stone and the way the ocean punches through the opening during high swells.
Ly Son itself is a volcanic island, and Cong To Vo is one of the clearest reminders of that geology. The surrounding rock is sharp and uneven, covered in patches of moss and sea salt. Locals sometimes call it the "gate" of the island's old volcanic rim, though geologists would probably argue with that label. Either way, it's become one of the most recognizable landmarks on Ly Son.
Why travelers go
People come here for the raw coastal scenery and the photography. The arch looks different depending on the tide — at low tide you can walk right up to the base and shoot through the opening toward open water. At high tide, waves crash through and spray kicks up over the rocks. Early morning light hits the arch from the east, which is the angle most photographers want.
But Cong To Vo isn't a full-day destination on its own. It's one piece of a Ly Son Island visit that includes garlic fields, volcanic craters, pagodas, and some of the freshest seafood in central Vietnam. Think of it as a key stop on the island loop, not a standalone attraction.
Best time to visit
The sweet spot is March through August. Seas are calmer, making the boat crossing from Sa Ky port smoother (important if you get seasick). June through August is peak season — the water around the arch turns a vivid blue-green and conditions are best for swimming nearby.
Avoid October through February if you can. Northeast monsoon winds make the crossing rough, and some boat services reduce frequency. The arch itself is accessible year-round, but stormy seas mean you won't get close to the water's edge safely.
For the best light at the arch specifically, go between 5:30 and 7:00 AM. By mid-morning the sun is overhead and the contrast flattens out.
How to get there
Cong To Vo is on Ly Son Island, so you need to get to Sa Ky port in Quang Ngai first, then take a speedboat.
From Da Nang: Take a bus or private car south along the coast — about 160 km, roughly 3 hours by car, 4 hours by local bus. Buses from Da Nang's central bus station to Quang Ngai city cost around 120,000–150,000 VND. From Quang Ngai city, grab a taxi or xe om to Sa Ky port, another 20 km east (about 150,000 VND by taxi, 30 minutes).
From Sa Ky port to Ly Son: Speedboats run daily, usually departing between 7:00 and 8:00 AM, with afternoon returns. The crossing takes about 30 minutes. Tickets run 170,000–200,000 VND one way. Book a day ahead during summer weekends — boats fill up.
On Ly Son: Rent a motorbike (100,000–150,000 VND per day) or hire a xe om. The island is small — about 10 km² — and Cong To Vo is on the northeast coast, a 10-minute ride from the main pier.
Photo by AN Nhol on Pexels
What to do
Walk the basalt shelf
The rock platform around Cong To Vo extends a good 100 meters along the shore. At low tide, tide pools form in the basalt crevices — sea urchins, small crabs, anemones. Wear shoes with grip; the rock is sharp and slippery.
Catch sunrise through the arch
Get there by 5:30 AM and you'll likely have it to yourself. The sun rises through the arch opening during summer months, which is the shot everyone wants. Bring a tripod if you care about that sort of thing.
Visit Chua Hang (Hang Pagoda)
About 1 km west along the coast from Cong To Vo, Chua Hang is a Buddhist pagoda built into a sea cave. The combination of incense smoke, dripping cave walls, and ocean sounds makes it one of the more atmospheric temple visits in central Vietnam. Free entry.
Walk through the garlic fields
Ly Son is famous across Vietnam for its garlic — the volcanic soil gives it a distinct flavor. The fields cover much of the island's interior, and during harvest season (March–April) the smell is everywhere. Bundles of fresh garlic sell for around 100,000 VND per kilogram directly from farmers.
Swim at Bai Sau (Back Beach)
On the south side of the island, Bai Sau has a sandy beach where you can actually swim comfortably. It's a good counterpoint to the rocky north coast around Cong To Vo. No entrance fee, a few drink stalls nearby.
Where to eat nearby
Ly Son's food scene is small but specific. Two things to seek out:
"Goi tom hum" (lobster salad): Ly Son lobster is smaller than what you'd find in Phu Quoc or Nha Trang (냐짱 / 芽庄 / ニャチャン), but it's fresh and cheap by comparison — a plate of lobster salad runs about 200,000–350,000 VND at seafood restaurants near the pier. Try Quan Hai San Ba Tam near the main dock.
Garlic shrimp: Basically every restaurant on the island does some version of shrimp fried with Ly Son garlic. Simple, good, around 80,000–120,000 VND per plate. Pair it with rice and a cold Saigon beer.
For something familiar, a bowl of "hu tieu" shows up at a few breakfast spots near the market — the southern-style noodle soup made its way here via traders from the Mekong Delta (메콩 델타 / 湄公河三角洲 / メコンデルタ).
Where to stay
Ly Son has guesthouses and a handful of small hotels, mostly clustered near the pier.
- Budget: Local "nha nghi" (guesthouses) run 200,000–350,000 VND per night. Basic but clean. Ly Son Hostel is a reliable option.
- Mid-range: A few newer hotels with air conditioning and sea views go for 500,000–800,000 VND. Muong Thanh Ly Son is the most established.
- No resorts. This isn't Phu Quoc (푸꾸옥 / 富国岛 / フーコック). The island's infrastructure is modest, which is part of the appeal.
Photo by ㅤ quang vinh ㅤ on Pexels
Practical tips locals would tell you
- Bring cash. ATMs on Ly Son are unreliable. Withdraw what you need in Quang Ngai city before heading to Sa Ky port.
- Sunscreen and water. There's almost no shade at Cong To Vo. The basalt absorbs heat and the reflected light off the water is intense.
- Check tide times. Low tide is better for exploring the rock shelf. Ask your guesthouse host — they'll know the schedule.
- Don't touch the coral. Some snorkeling spots around the island have recovering reef. Guides will tell you this; listen to them.
Common mistakes to avoid
- Wearing flip-flops to the arch. The volcanic rock will cut your feet. Bring proper sandals or water shoes with rubber soles.
- Only planning a day trip. The boat schedule makes day-tripping tight. One night on the island lets you catch sunrise at Cong To Vo and explore properly.
- Skipping Be Island (Dao Be). If boats are running to the smaller island northeast of Ly Son, go. It's quieter, the water is clearer, and fewer people make the trip. Boat fare is around 100,000 VND round trip.
Practical notes
Ly Son is still relatively low-key compared to more developed Vietnamese islands. Cong To Vo takes maybe 30 minutes to explore on its own, but the island around it fills a solid two days. Combine it with a few nights in Quang Ngai city or work it into a longer central Vietnam route between Da Nang (다낭 / 岘港 / ダナン) and Quy Nhon.
Last updated · May 19, 2026 · independently researched, never sponsored.
