When I crossed the border on a passenger train from Poland to Belarus and from Mongolia to China, the train went into a warehouse where the compartment was lift

When I crossed the border on a passenger train from Poland to Belarus and from Mongolia to China, the train went into a warehouse where the compartment was lifted and new bogies slid underneath. All while the passengers remained on the train https://www.flickr.com/photos/mjdoughty/8502710543/ https://www.flickr.com/photos/mjdoughty/8502710543/