Tekdag-aso Falls is located in Bacnotan, La Union, Philippines.

Tekdag-aso which is located west of the bedrock. In Iloco it means Tinnag-aso which means Hulog-aso in Filipino and Fall-dog in English. It is called so because according to elders, it is a perfect trap for dogs which is a favorite local delicacy. Once a dog falls into the deep, circular and high primary basin made up of solid rock, the poor victim can no longer escape and eventually die of drowning. Going down lies the wide and enchanting secondary basin which is most perfect for swimming.

Source:

Launion.gov.ph