Question: If I have a day or two to spare from my stay in Shanghai, how can I tour Zhouzhuang and Suzhou? How can I get there and get back easily? How far is Zhouzhuang from Suzhou? How can I tour the two places on one trip? Where would be a good place to eat in Suzhou?
Update 2022-02. If you go by high-speed G trains, travel time between Shanghai and Suzhou is just 25 minutes. Dozens of departures from Shanghai Railway Staiton and Shanghai Hongqiao Railway Station. Arrivals at Suzhou Railway Station and Suzhou North Railway Station.
Answer: Zhouzhuang is located in between Shanghai and Suzhou. It is about 60 km east of Shanghai and 40 km or so southwest of Suzhou. From either Shanghai or Suzhou, it is a bus trip of about a hour. So, you can travel to Zhouzhuang from Shanghai or Suzhou rather easily. You can visit Zhouzhuang first and then move on to Suzhou or do it in the reversed order. In Shanghai, you should be able to find Zhouzhuang-bound buses at Shanghai Changtu Keyun Zhan (Shanghai Long-Distance Bus Passenger Transportation Station) or Ba Wan Ren Tiyu Chang (Eighty Thousand People Stadium). In Sunzhou, you should be able to find buses you need at Suzhou Qiche Bei Zhan (Suzhou North Bus Station).
If you want to tour both Zhouzhuang and Suzhou, you'll need two or three days. Zhouzhuang is a small place, known as a "water town," with a dozen or rivers running through it and quite a few bridges. You can walk about in the town, take in the local flavor, and finish the tour in one day. If you have time, you can stay overnight in Zhouzhuang so that you can go to a couple of local performances or sail in a boat in the evening. Otherwise, you can move on to Suzhou on the same day and spend the night in Suzhou.
Suzhou is a city of 2 million people (not including the suburbs and surrounding countryside). In China this makes it a mid-sized city (on the small side). The main attraction in the city is traditional gardens - Huqiu (Tiger Hill), Zhuozhengyuan (Garden of the Humble Official), Xiyuan (West Garden), Liuyuan (Liu Garden), Changlangting (Pavilion of Waves), Hanshansi (Temple of Cold Hill). It takes about one day for one to tour these attractions. On the next day, you can do some more sightseeing in the city or go to Taihu (Tai Lake) and spend a little there (Taihu is one of the largest lakes in China; it is a short distance outside Suzhou). So, ideally, you have two days to visit Suzhou; you can, of course, select a few attractions and wrap up your tour in one day and then return to Shanghai in the evening. You can travel between Shanghai and Suzhou both by coach or by train. By train, the distance between Shanghai and Suzhou is 85 km; train travel time is about an hour.
As for food in Suzhou, on Guanqian Jie (Guanqian Street) and Taijian Nong (Taijian Lane) there are is a heavy concentration of restaurants, which offers a great variety of cuisine. The nearby Fenghuang Jie (Fenghuang Street) is also lined with many good restaurants. These streets are located in the heart of Suzhou.