A Shenzhen Metro engineer inspects a new Line 3 train during Monday's test run. Trains for Metro Line 3 started trial running, signaling the countdown to the official opening of the Metro line. Costing nearly 9.9 billion yuan (US$1.45 billion), Metro Line 3 covers nearly 33 kilometers, starting at HongLing Road Central in Futian District and winding through Luohu District before ending at Longxing Street in Longgang District.