Zim-sim-ug Falls is located in Bacnotan, La Union, Philippines.

The falls has an estimated height of 20 feet and a basin deep of eight to nine feet. It got its name from the Kankanaey dialect which in Iloco means Timtim-ug. In Filipino, it means nag-uumpugan which literally means banging of heads. According to the locals, it was named so by their ancestors because of the rocks that collide at the common basin of the rare twin waterfalls. Because of its continuous water supply, farmers use the water sources above the waterfalls to irrigate their fields.

Source:

Launion.gov.ph