boats of local fishers were harbored in the rocky beach in toba lake, north sumatra, indonesia

areas batak beach beaches boat buhit caldera capturing catching clear commonly covered crystal dark feed fisherman fishes found freshwater geopark grow harbor harbored indonesia island lake local monochrome moss net north pangururan pusuk rock rockies rocks rocky samosir submerged sumatera sumatra supervolcano tapanuli tilapia toba traditional using water weeds