This location marks a memory created by Dr Yun Tsun, it is difficult to say what "symmetrical garden" he is referring to exactly. Hai Feng is a coastal region of southern China in the Shanwei province. Renowned for it’s luciousness.
It is interesting to note that this memory is not linked by geolocation to the one of his ancestor Ts'ui Pen. There are however, repeated references throughout Tsun’s letter of gardens. Seeing the garden is something left for further reading.