Pakistan's first metro line has begun commercial operations in the eastern city of Lahore.
The 27km (17-mile) Orange Line, with more than two dozen stations, will drastically cut travel time across the notoriously congested city, reducing a two-and-a-half-hour bus journey to 45 minutes by metro.
Officials expect about a quarter of a million people will use the system each day once it is fully operating.
"This project will provide world-class facilities to the public in Lahore," Punjab state's chief minister Usman Buzdar said during Sunday's inauguration ceremony.
The project cost 300bn rupees (£1.4bn; $1.8bn) and welcomed its first paying passengers on Monday after years of delays and political controversies.
It was built with Chinese backing and there are growing questions about the huge amount of debt Pakistan has taken on in recent years.
China has invested tens of billions of dollars in Pakistan as part of its Belt and Road Initiative which aims to link the economies of Asia, Africa and Europe via huge infrastructure projects.
The metro project led to protests from people concerned it would damage some of Lahore's most famous landmarks, in particular the Shalimar Gardens, a world heritage site. More than 600 trees had to be felled along the route.
Speaking at the inauguration, Chinese Consul General Long Dingbin called the metro system a milestone in Pakistan-China friendship.
"I congratulate the Punjab government and the people of Pakistan on this occasion," he said.
Chinese state news agency Xinhua called the Orange Line the beginning of "a new stage for the South Asian country in the public transportation sector".