Hello how may I help you? Where is the tallest indoor waterfall located? It is located in the Heart of Singapore. Where is the tallest Waterfall? The worlds tallest waterfall is Angel falls in Venezuela. Where in the heart of Singapore is the tallest indoor waterfall? It is in Singapore. Singapore is not indoors Waht is the name of the building this indoor waterfall is in? Orchard road is known as the Heart of Singapore. The tallest indoor waterfall is in Singapore Gardens that is in the Heart of Singapore. Thank you You're welcome!