How long does Line 9 take from Hongling North to Shenzhen Bay Park?
About 34 minutes.
According to Baidu map, get on the bus from Honglingbei subway station, take subway line 9 (direction of Qianwan), pass 12 station, and get off at Shenzhen Bay Park subway station. The whole journey is about 16.6 km, and it takes about 34 minutes.