The tunnel is home to four out of the six mangrove species native to Taiwan, with the Rhizophora stylosa being the most dominant.
The waterway was historically part of a transit canal system used by merchant vessels during the Qing Dynasty era.
The 'Green Tunnel' effect is achieved through the specialized growth patterns of mangroves that thrive in brackish tidal environments.
The area is officially part of the Taijiang National Park, established to preserve both ecological and cultural heritage.
The water depth in the canal is intentionally maintained at a shallow level to support the specific growth needs of the mangrove root systems.
The Sicao Green Tunnel is a protected mangrove waterway located within the Taijiang National Park in Tainan, Taiwan. It features a dense, natural canopy formed by interweaving branches of four types of mangroves—Rhizophora stylosa, Avicennia marina, Kandelia obovata, and Lumnitzera racemosa—overhanging a narrow canal. Historically utilized as a transportation route during the Qing Dynasty, this site now functions as an ecological preserve accessible via guided bamboo raft tours. The passage creates a mirror-like reflection on the water's surface when winds are calm. Visitors observe a variety of local wetland wildlife, including fiddler crabs, mudskippers, and various species of migratory birds. The site serves as a vital environmental education hub for regional mangrove biodiversity.
The mid-point of the tunnel, where the density of the branches creates a perfect symmetrical 'eye' shape reflecting on the water.
Wear a hat and apply high-SPF sunscreen, as the shade from the canopy is inconsistent and the reflected sunlight on the water is intense.
Bring mosquito repellent, as the humid, stagnant-air environment of the mangrove swamp is a common habitat for insects.
Arrive early in the day to beat the large tour groups that arrive by motorcoach.
Avoid the mid-afternoon heat during summer months and do not attempt to touch the mangrove branches or wildlife.
Operations are suspended during typhoons or severe weather events; boat schedules are often adjusted based on tidal levels.
Life jackets provided by the operators must be worn at all times while on the boat; remain seated during the transit to maintain vessel stability.
