Indonesia is launching Southeast Asia’s first high-speed railway, a key project under China’s Belt and Road infrastructure initiative that will cut travel time between the capital and another major city from the current three hours to about 40 minutes.

The project has been beset with delays and increasing costs, and some observers doubt its commercial benefit, but President Joko Widodo has championed it and will be inaugurating the 142.3-km railway as it begins commercial operations on Monday.