mahakam river stone wall, borneo, indonesia

watercourse waterway boating stream river water coast shore rapid canal cliff tree pond sea bay mahakam ulu regency capital ujoh bilang east kalimantan geographical inland areas protected forest long bangun samarinda tering port batu dinding sungai towering steep wall rocks limestone banks rock stretches fight current bury victims dangerous rapids center hilly stilt wood roofs shingles houses residents store firewood original inhabitants dayak tribe kenyahkayan bahau indigenous heritage karst hang ancient tombs