Passengers taking the high-speed sleeper train D910 bound for Beijing West Railway Station pose for a selfie at Hong Kong's West Kowloon Station in Hong Kong, south China, June 15, 2024. High-speed sleeper trains linking Beijing and Shanghai with Hong Kong commenced operations on Saturday.

The time it takes to travel between Beijing and Hong Kong is reduced to 12 hours and 34 minutes, and the travel time between Shanghai and Hong Kong to 11 hours and 14 minutes.

With the new services, passengers are able to travel between the Chinese mainland and Hong Kong overnight. (Xinhua/Wang Shen)

The high-speed sleeper train D909 bound for Hong Kong's West Kowloon Station departs from Beijing West Railway Station in Beijing, capital of China, June 15, 2024. (Xinhua/Zhang Chenlin)

Passengers taking the high-speed sleeper train D910 bound for Beijing West Railway Station pose for photos at Hong Kong's West Kowloon Station in Hong Kong, south China, June 15, 2024. (Xinhua/Wang Shen)

Passengers boarding the high-speed sleeper train D907 bound for Hong Kong's West Kowloon Station wave good-bye at Shanghai Hongqiao Railway Station in east China's Shanghai, June 15, 2024. (Xinhua/Wang Xiang)

Passengers display gifts they received onboard the high-speed sleeper train D910 bound for Beijing West Railway Station, in Hong Kong, south China, June 15, 2024. (Xinhua/Wang Shen)