Does SouthESIM work on China's High-Speed Trains (Gaotie)?

Yes, generally your SouthESIM will work well on China's high-speed trains, known as Gaotie! You can expect to have 4G/5G connectivity while traveling between major cities like Beijing and Shanghai, which is great for browsing or staying in touch. However, it's common for the signal to become intermittent or temporarily cut out when the train passes through longer tunnels or mountainous regions. So, if you have important work, we recommend downloading it beforehand.