Recently, China’s National Development and Reform Commission issued a notice that detailed efffforts to promote new urbanization during the 14th Five-Year Plan period (2021-25), proposing to build an integrated transportation network for city clusters, and to accelerate the construction of intercity railways and urban/suburban railways in the Beijing-Tianjin-Hebei, Yangtze River Delta, Guangdong-Hong Kong-Macao Greater Bay Areas, and to promote the multilevel rail transit network construction of the Chengdu-Chongqing economic circle and other key urban clusters, adding 3,000 kilometers of intercity railways and urban/suburban railways by 2025 and basically achieving 2-hour access between major cities . Under the local fifinancial and economic conditions, many cities have put forward specifific goals in developing intercity railways and urban/suburban railways. For Beijing, the total mileage of its operational urban/suburban railways will strive to reach 600 kilometers by 2025; for Shanghai, the total mileage of its operational urban rail transit lines and urban/suburban railways will reach 960 kilometers by 2025; for Guangzhou, an over-1500-kilometer rail transit network consisted of subway lines and intercity railways will be completed between 2025 and 2030; and for Chengdu, an over-1666-kilometer rail transit network will be built by 2050, including 7 urban/suburban railways totaled 277 kilometers. Faced with the golden opportunity for the construction of intercity railways and urban/suburban railways, how can we learn from the past to promote its scientifific and sustainable development? The 16th Annual City-Rail Summit, under the theme of 'Multilevel Rail Transit Network Construction: Intelligence · Integration · Interconnectivity · Interoperability', will invite rail transit-related authorities, construction and operation units, planning and design institutes, investment and fifinancing entities, and high-tech solution providers, to discuss the diffiffifficulties and opportunities of intercity railways and urban/suburban railways in planning and construction, system standards, equipment and technologies, and operations management, jointly promoting the coordinated, green, intelligent and sustainable development of rail transit, urban clusters and metropolitan areas.