In a river terrace in a mountainous part of Tahsi Township in Taoyuan County, a stream trickles through a gully from a deep depression at the base of Mt. Paishih, first flowing into narrow Rear Tzuhu lake, then spilling over a curved ridge called Dragon Pass before flowing into Front Tzuhu.
桃園縣大溪鎮鄰近山區的河階台地，一條溪澗從山坳深處的白石山麓緩緩涓流而出，先流入上游狹長的後慈湖，再溢流經過一條名為「龍過脈」的彎曲田壟，流入前慈湖。