If you can only visit one place in Suzhou, I suggest this. It has all the "typical" Suzhou things you want to see. It has an old gate, some walls, some canals, a pagoda, a lake, gardens, walking paths. It's a nice place. There is even a classic show and fireworks at night (which are included in the entry fee whether or not you're there when the shows take place).
And all for 40rmb.
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