In the past Chinese has been written on rolls of bamboo sticks which made it easier to write the characters vertically and from left to right. And this is the way how text is arrayed in Taiwan, Hong Kong and Japan unti now, while Mainland China has adopted the writing from left to right and top to bottom. But in temples for example you will still see the top to bottom and vertical writing in China.
Here is 將進酒 / 将进酒 (Bringing in the wine), my favourite Tang poem by Li Bai in tne traditional form:
