At first glance, visitors to the new Jewel complex at Singapore’s Changi Airport might feel like they have entered some mythical dimension. An indoor waterfall — the tallest in the world — drops 130 feet from an oculus the size of a bus. A Canopy Park has nets for bouncing and walking strung as high as 80 feet above the ground. A forest of 1,400 trees provides greenery and shade.

The multi-floored Jewel, an asymmetrical toroid-shaped building between the airport’s existing terminals and the air-traffic control tower, opens officially on April 17. The result of four years of construction and $1.25 billion in investment, the commercial and entertainment structure aims to do what no other building has done: make an airport the destination.

“Singapore is a tourist destination, but 30 percent of the people coming through Changi don’t visit,” said Ivan Tan, a senior vice president for Changi Airport Group. The country wants to draw those passengers on connecting flights, get them out to experience a taste of Singapore, so that they might come back for a longer stay.

The centerpiece of the building is the Forest Valley with a terraced garden, and its heart is the Rain Vortex waterfall. The top floor, called Canopy Park, features bouncing and walking nets, a 165-foot sky bridge, two mazes (one with mirrors, the other hedges), a giant slide, and eight bars and restaurants. The exterior of the 10-story building, which was designed by the architect Moshe Safdie and built by CapitaLand, an Asian developer, is made of glass and crisscrossed with an aluminum-and-steel framework, allowing the entire interior to be bathed in natural light.