My favourite waterfalls? My answer is always the same: Iguazú Falls in Argentina, Windin falls in Australia and Tumpak Sewu in Indonesia.
At first, you have an overlook where you can get to see the falls from above with the Mount Semeru in the background, one of the many volcanoes of Indonesia. After a sketchy hike, you arrive to the bottom of the falls where you fell the magnitude of Tumpak Sewu. The towering walls on either side of the ravine let you know how tiny you are.
East Java, Indonesia.