Meigetsu-in, a small temple located in North-kamakura, has a really nice window. The window is round, which in Buddhist terminology means to be complete or perfect.
Besides this very famous round window, Meigetsu-in is also known for its hydrangea flowers, which bloom in June. The temple has a reputation for being one of the most beautiful and sublime in Kamakura, and indeed in all Japan, and is worth a visit each season throughout the year.
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Find out more about Meigetsuin Temple.