All cars are air-conditioned. Traveling between two cities, you can take in the view through the large windows, and enjoy comfort you won't find in air travel. Most trains also carry a cafe, in which you can order hot and cold snacks, sandwiches, beer and alcoholic drinks, and a wide range of non-alcoholic beverages.

The vast majority of modern passenger trains—including high-speed, regional, and commuter rail—are equipped with advanced HVAC (Heating, Ventilation, and Air Conditioning) systems. These systems are typically roof-mounted or under-floor monoblock units that regulate temperature and humidity to ensure passenger comfort in diverse climates. High-speed networks like the Shinkansen, TGV, and Eurostar use high-performance, lightweight AC units with precision controls. In some older "heritage" trains or specific regional networks in developing nations, AC may be limited or reserved for "first-class" carriages, while standard coaches rely on open windows and fans. However, in 2026, AC is considered a global industry standard for new rolling stock to enhance the quality of rail travel and reduce indoor air pollutants. Many modern trains even feature "smart" climate control that adjusts based on the actual passenger occupancy of the car to save energy while maintaining a high-fidelity environment.