玄冬の鶴丘、緑は漆黒へと Deepening winter, corresponding to Xuanwu in feng shui Hachiman trees are also to jet black

Kamakura, which is said to have been made on the basis of feng shui. 

Tsuruoka  Hachiman Shrine behind mountain is Xuanwu. 

Xuan color is black, season means the winter.