Tufa is a porous sedimentary limestone rock. In limestone areas, tufa is a porous carbonate deposit (a kind of limestone) formed from freshwater sources such as spring and river water. Cyanobacteria (photosynthetic bacteria) are involved in its formation.
At Fumidakahra River, there are various forms of tufa, such as the pea-shaped tufa, the waterfall-shaped tufa with a drop of more than 3 m, and the terrace-shaped tufa.
The tufa in the Fumidakahra River is the largest in Okinawa Prefecture and is an important natural monument for the geological history of Ishigaki Island.
Ishigaki City ordinance prohibits altering the current state of the designated area, such as by taking out pea-shaped tufa or damaging the formed tufa. During your visit of this area, you are highly recommended to understand its scientific importance and to pay extra attention not to step on and damage the tufa.

Let’s enjoy the scenery around Ishigaki Island through 360-degree photos!

Back to the 16th TARF Open House (Online)

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