Emerald Lake

　　Emerald Lake is a high-altitude alpine lake located in Taiwan’s Snow Mountain Range. With a cirque slope to the south and a raised embankment to the north, it is inferred to be a cirque lake formed by glacial erosion. Situated within Shei-Pa National Park in Tai’an Township, Miaoli County, it sits at an elevation of 3,520 meters, making it the highest natural lake in Taiwan.

　　The lake is oval in shape, with an opening to the north where water collects and flows downward, forming the Sian River. The waters of the Sian River converge with those of the Daxue River and the Madala River before flowing into the Da’an River. To the northeast, there are two raised embankments extending northwest, each about 50 to 60 meters long and 3 meters high. The Sian River passes through these two embankments, creating a small gorge. To the south is a scree slope, part of the Snow Mountain No. 7 Cirque, which stores groundwater runoff and serves as the source of the lake’s water.

　　The lakebed is covered with slate fragments, which is why it is called “Siron Hagai” in the Atayal language, meaning “stone pool.” The entire lake is approximately 40 meters long and 20 meters wide. Its water level varies depending on rainfall; during wet seasons, it can reach a depth of 1 meter, while in dry periods, only the central depression retains water. However, it never dries up completely and remains unfrozen even in winter. The surrounding area is home to Taiwan’s largest pure stand of Taiwan juniper (Juniperus formosana), featuring towering trees and spectacular scenery.

　　CuiChi Reason to Visit: The highest natural lake in Taiwan