There’s some very nice running at Suzhou Taihu National Wetland Park, located in the Huqiu District west of Suzhou’s urban core, adjacent to Taihu Lake and the Zhenhu Lake area. The trail system consists of a network of wooden boardwalks and paths that wind through the wetland habitat, connecting scenic zones, bridges and overlooks. Note: Set hours & possible admission fee. 

The park website describes an 8 km park loop, mainly on a wooden boardwalk. There’s nice scenery and greenery, and a botanical garden section. There are restrooms and other facilities. 

NOTE: We also have routes at the northern end of Taihu Lake, closer to Wuxi.