Batu Caves, Malaysia
The limestone forming Batu Caves is said to be around 400 million years old. Some of the cave entrances were used as shelters by the indigenous Temuan people (a tribe of Orang Asli).
As early as 1860, Chinese settlers began excavating guano for fertilising their vegetable patches. However, they became famous only after the limestone hills were recorded by colonial authorities including Daly and Syers as well as American Naturalist, William Hornaday in 1878.
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