Passengers in Terminal 4 have to go to Terminal 2 first by Airport Shuttle Bus and then get to Level 3 to find the link bridge to get to Jewel. But whether you are an airline passenger or not, the Jewel Rain Vortex located under a huge dome in Jewel Changi Airport is a must see.

To get to the HSBC Rain Vortex at Jewel Changi Airport from Terminal 4, you must first take the complimentary shuttle bus to Terminal 2, as Terminal 4 is a standalone building not physically connected to the main airport complex by foot or Skytrain. The shuttle bus operates 24 hours a day and departs from the T4 arrival hall. Once you arrive at Terminal 2, follow the clear overhead signage for "Jewel." You will need to walk through a glass-enclosed link bridge (Level 2) that connects T2 directly to the Jewel complex. The walk takes about 5 to 10 minutes. The Rain Vortex is located at the very heart of Jewel. Note that Jewel is in the public area (landside), so if you are a transiting passenger, you must legally clear immigration to visit it. Once inside Jewel, the waterfall is visible from almost every level, but the best view is from the Shiseido Forest Valley at the basement or Level 1.