Hi Keiko, When we emphasise the fact that someone or something is famous for a particular quality, we use "known for". Example: Japan is known for cherry blossoms. When we want to associate someone or something with another label, we use "known as". Example: Rowan Atkinson is known as Mr Bean. In your example, Kyoto was an ancient capital of Japan.It is a label (capital) which we ascribe to Kyoto. Hence, we use " known as". In contrast, Kyoto is "known for" its beautiful temples. Now, Kyoto is famous in many people's minds for a quality -- beautiful temples. Hope this helps. Cheers, Lance

"A is known as B." We expect B to be a description of what A _is._ Often, B would be an alternative name or nickname of A. "A is known for B." We expect B to be a description of what A _has_ or _does._ Paris is known as "the City of Light." Paris is known as the capital of France. Paris is known as the fashion capital of the world. Paris is known for the Eiffel Tower. Paris is known for its world-renowned cuisine. Paris is known for its art museums. Do you understand why this would not only be wrong, but silly? Paris is known as the Eiffel Tower.

'Known as' is used to express the idea of an alternative name, or a descriptive phrase. 'Known for' is used to list attributes or characteristics that something or someone is famous for. So - I can understand your confusion, as being an ancient capital is somewhat between those two ideas. I don't think that it is a very good question, and does not really use 'as' in the way I would. But - if I had to pick one, 'as' is the best option. I would say 'Kyoto is known as the Venice of Japan', or 'Kyoto is known for its kaiseki'.