A shrine is the holy place of the Shinto religion. Shinto is very much connected to nature. There are gods for everything. According to an ancient Japanese belief, mother earth has to be impregnated by father heaven, so that everything can grow and develop. Local farmers come and pray for a good harvest at this shrine.
Some believers ask for good birth or a healthy baby.
You can't see images that represent God in a shrine, like the statues in Buddhist temples. The only things visible are symbols that represent the chores of a Shinto god. The symbols, made of wood or stone, in the Tagata shrine are phallic. There are lots of them, from tiny, small ones to very big ones. The symbol of fertility, they all stand erect.