South Lake is Jiaxing's best-known sight and, unusually for a Chinese scenic lake, carries genuine political history alongside its classical gardens and pavilions. The lake is divided into an outer expanse and an inner enclosure dominated by Yanyu Lou — the Misty Rain Pavilion — a multi-storey painted wooden tower on a mid-lake island, connected to the shore by a stone bridge. The pavilion dates from the Song dynasty and has been rebuilt repeatedly, and the reflection of its tiered eaves in the still water is the standard Jiaxing image.
The Red Boat Memorial is moored at the lake's southern shore — a reproduction of the passenger boat where the Chinese Communist Party held the final session of its First National Congress in 1921. Chinese tourists treat this with a reverence bordering on pilgrimage, and the site includes a museum charting the party's founding with photographs, documents, and wax figures of the thirteen delegates. Non-Chinese visitors tend to find the historical context more interesting than the memorial itself, but the context is genuinely remarkable: an organisation forced onto a tourist boat by Qing-era police went on to govern the world's most populous country.