Changshu (; Suzhounese: /d͡ʐan¹³ ʐoʔ²³/) is a county-level city under the jurisdiction of Suzhou, Jiangsu province, and is part of the Yangtze River Delta. It borders the prefecture-level city of Nantong to the northeast across the Yangtze River. Due to the mild climate and terrain there, it has enjoyed a high level of agricultural civilization since ancient times, and is named after this, for the first character of its name (常) means "always, often", while the second (熟) means "ripe". The name of the adjacent county-level city of Taicang means "great granary".