PLACE GUIDE

Sanmenhai 三门海

Sanmenhai is experienced from the water.

Turquoise karst sinkhole lake surrounded by cliffs at Sanmenhai
A turquoise sinkhole lake enclosed by karst cliffs at Sanmenhai, Fengshan County, Hechi, Guangxi. · 广西河池凤山县三门海天窗，喀斯特峭壁环绕的碧绿水潭。 Source-recorded photograph date: 2012-08-17. · Rosysea · CC BY-SA 3.0
Photo adjustments

Full frame retained; proportionally resized and converted to WebP. No retouching or changes to the photographed subject. Card displays may crop the view.

Explore the region

Guangxi · 广西壮族自治区 →Hechi · 河池市 →

About Sanmenhai

A boat follows the Poxin underground river through low limestone passages, then emerges beneath openings where daylight, trees and sky suddenly replace the cave roof. The wider system contains seven karst skylights, while the described visitor boat route enters three. The contrast between enclosed passage and open, green-edged water is the attraction; use the managed boat trip rather than assuming every opening in the system is accessible.

Sanmenhai forms part of Fengshan County National Geopark (凤山县国家地质公园). Its water lies within a karst landform. The name, meaning 'three-gate sea', refers to three skylights through which it can be entered and to the water's sea-like colour, depth and tidal behaviour.

What to look for

  • Low cave passages alternate with large natural openings overhead.
  • Daylight and trees around the skylight rims contrast with the enclosed underground river.

Location & getting there

Getting to Sanmenhai

Go to the Sanmenhai visitor boat departure point at Poxin Village, Sanmenhai Town, Fengshan County. The cave circuit begins from the managed village-side jetty; confirm the operating boat route on arrival.

General visit reminders

Allow room for the terrain and weather when choosing your route. Check the operator’s current trail, shuttle and cableway notices where applicable, and confirm the return connection before setting out. A broad landscape pin does not identify every trailhead or access point.

Combine your visit

Suggested order for the visit:

  1. Village-side jetty

    Join the managed boat circuit.

  2. Underground passage

    Notice the low limestone roof above the river.

  3. Open skylight section

    Look up to the natural rim before the boat completes its authorised route.

This is an editorial sequence of named spaces or places. It does not imply a verified walking connection or promise opening, ticket availability or a journey time.

Landforms & caves · 地貌／洞穴 →

Find Sanmenhai

三门海 · 河池

Amap · 高德地图Approximate pin · 近似位置Apple Maps · 苹果地图

The pin marks the area, not the entrance.

More places nearby

Approximate straight-line distances between map pins, not travel distances.

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Sources & visit information

The sources below support the place-specific description and arrival information. Suggested combinations are editorial planning ideas; confirm current opening, entry arrangements and transport services for your date.

Background paragraphs translated and condensed from Wikipedia contributors, "三门海", Chinese Wikipedia · CC BY-SA 4.0. Source revision 79022648.

China Revealed · Editorially updated 2026-10-07