Ryoanji temple was originally a country house of the Tokudaiji Clan, it was acquired in 1450 by Katsumoto Hosokawa for use as a Zen training temple. This temple was registered as a World Heritage Site in 1994.
Going through the main gate, you can see the Kyoyochi Pond, which was made in the late twelfth century. Until recent years many mandarin ducks were to be seen on the pond. Lotus flowers are beautiful. 
The rectangular Zen garden is made from only 15 rocks and white gravels.
Then, let's count the number of rocks in practice.
How many could you see? In fact, it is impossible to see all 15 rocks at the same time in this garden. In the old time Japan, the number 15 means "perfect." And it is said that this garden expresses "imperfectness of the world" even though this story is just one of many interpretations of the garden. The constructor of this garden is unknown, and its interpretation is entrusted the person who appreciates this garden.
On the back side of the garden, there is a "Tsukubai," which is the stone wash-basin for the tea room. It has a unique inscription, "I learn only to be contented." This means, he who learns only to be contented in spiritually rich, while the one who does not learn to be contented in spiritually poor even if he is materially wealthy. This is Zen spirit. 
The temple is open 8:00a.m. - 5:00p.m. from Mar to Nov, and 8:30a.m. - 4:30p.m. from Dec to Feb. Admission fee is JPY500 for adult and JPY300 for children under 15.
Experience Japan!