Located near Turpan in China's Xinjiang region, Jiaohe Ruins, also known as Yarkhoto, is the world's largest and best-preserved ancient earthen city. Carved straight down into loess instead of built up with bricks, this 2,300-year-old oasis city once stood as a vital Silk Road hub. Its unique terrain formed a natural fortress without city walls. These quiet ruins still tell stories of trade, Buddhism and cross-cultural exchange along the historic route. Photos: Cui Meng/Global Times