Their numbers could help tourists plan trips when clouds are more likely to form and surround the castle, enhancing the picturesque beauty of the historic site. Bitchu-Matsuyama Castle is located along the Takahashigawa river near the 487-meter peak of Mount Gagyuzan. A sea of clouds may cover the area on mornings from late September through early April, but the peak season is from October through December. The clouds are prone to form when a number of conditions are met, including: calm wind in the altitude range of 1,000 to 2,000 meters; a large temperature difference between daytime and night on the previous day; and clear weather on the previous night. But the formations are not guaranteed, and many early morning visitors who throng a mountain observation deck 1.1 kilometers from the castle can leave disappointed.