On the east side of a vast concrete plaza that welcomes visitors to the Tsingpu Yangzhou Retreat, a rectangular opening cut into a gray brick wall frames a lone tree and reflecting pool—a preview of the landscape that lies beyond the square, within this hotel’s internal grid of brick-walled passageways. In fact, the property features 45,000 square feet of courtyard spaces, with trees, terraces, pools, and 20 spalike guest rooms.