Indonesian President Joko Widodo inaugurated Southeast Asia's first high-speed railway connecting Jakarta and Bandung.
The project, funded largely by China, is part of the Belt and Road infrastructure initiative.
The 142-kilometer railway will reduce travel time between the two cities from 3 hours to about 40 minutes.
It operates at speeds of up to 350 kph and is named "Whoosh" for its efficiency and reliability.
The project faced delays and cost increases but is expected to reduce carbon emissions.
China will transfer technology to Indonesia for future high-speed train production.
Ticket prices are estimated to range from 250,000 to 350,000 rupiah.
The rail deal was signed in 2015, with China financing 75% of the cost.
The project is part of a larger 750-kilometer high-speed train line across Java.China's investment in Southeast Asia's infrastructure is expanding under the Belt and Road policy.