Surrounding nature of Blue Lake (Lom Phukeow) is dry evergreen forest. There are many wild animals. Villager walked and found this emerald green pool under the hill, so called “Lom Phukeow”. There is hill at the opposite side but don’t have water, so called “Lom Lang”. Villagers believed that Blue Lake is the holy pool and have King of Nagas lived there, so they have yearly water ceremony. There is tale from elder person that in the past village take bowl of rice with flower, incense stick and candle to pay respect. They put it on the log and let it flew to the middle of water. Then log sank and floated but candle still had light. They believed that this is holy pool and took water for drink and pray for get well. They also used in holy ceremony from past till now. Surrounding Blue Lake is limestone cliff, shady from large tree, quiet forest, stable of emerald green deep water which provide the beautiful place. Blue Lake is nature tourist place in Phathai Cave National Park, Lampang. There is large pool with area 1-2 Rai. The undefined dept let us can see the water in emerald green color. Assume that this pool cause from earth crust subside in prehistory or may cause from limestone cave ceiling subside and sink, called “Sink Hole” Then become receive water source and there are many fish in there.