What is Ganh Da Dia and how do I get there from Tuy Hoa?
Ganh Da Dia is hexagonal basalt columns on Phu Yen's coast — formed by volcanic lava cooling 200 million years ago, like Ireland's Giant's Causeway. 40km north of Tuy Hoa in An Ninh Dong, Tuy An. Entry: 40,000 VND. From Tuy Hoa: motorbike on Highway 1A north (~50 min), or taxi 250,000–350,000 VND one-way. Go before 9am.
The photographs don’t quite prepare you. Ganh Da Dia’s hexagonal basalt columns rise from the water in clusters — tight-packed, geometric, dark against the sea. The pattern runs for several hundred meters along the coast. It’s geological, not constructed, but it looks like something deliberate.
What it is
Ganh Da Dia is a coastal reef formation in An Ninh Dong commune, Tuy An district, on the northern coast of Phu Yen. The columns are basalt — volcanic rock that formed when lava cooled and contracted, fracturing into the characteristic hexagonal cross-section. The same process created Giant’s Causeway in Northern Ireland and Fingal’s Cave in Scotland. Phu Yen’s version is less known internationally but comparable in scale and visual impact.
The formation is roughly 200 million years old. The columns stand at heights of 1–5 meters above sea level and extend into the water for another few meters at low tide.
Getting there from Tuy Hoa
By motorbike: Follow National Highway 1A north for approximately 35km, then look for signs toward An Ninh Dong and Ganh Da Dia. The turnoff heads east toward the coast. Total from Tuy Hoa: 40km, approximately 50 minutes.
By taxi: One-way from Tuy Hoa city center runs 250,000–350,000 VND. For a day trip to multiple northern sights (Ganh Da Dia + Dam O Loan + Hon Yen), hiring a motorbike taxi for the day (500,000–700,000 VND) is more economical.
From Nha Trang by day tour: Tour operators in Nha Trang run day trips. These arrive by 10am, spend 45 minutes at the site, and return. Efficient but removes the option of early morning light or combining with other stops at your own pace.
At the site
The site has a parking area, ticket booth (40,000 VND adults), and a path to the formation. The walk from parking to the main reef takes about 5 minutes. The columns are accessible — you can walk among and on them — though the surface is uneven.
Photography: Low morning light is transformative. The shadows between columns define the hexagonal geometry. Midday light collapses the contrast and the formation looks like a grey mass. Wide lens (16–24mm equivalent) captures the full reef with sea in the background. ND filter useful for smooth water between the rocks.
What to avoid: Weekends and national holidays in peak season (March–June) when groups are large. Arrive at opening (6am) for the best experience.
Combining with other sights
Ganh Da Dia fits naturally into a northern day loop from Tuy Hoa:
- Ganh Da Dia (7–9am)
- Hon Yen (9–11am, if tide allows)
- Dam O Loan for oyster lunch (11:30am–1pm)
- Return to Tuy Hoa for afternoon